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Encyclopedia > Geothermal gradient

penis, hahaha big long penis. hahahahaha!!! The geothermal gradient is a ratio describing the rate of heating or cooling of the Earth's top soil and rock layers the deeper you go down, for instance by descending into a cave or drilling a well. The geothermal gradient is measured by taking a series of bottom open-hole temperature measurements during the drilling of a borehole. To achieve accuracy the drilling fluid needs time to reach the ambient temperature. This is not always achievable for practical reasons. In stable tectonic areas in the tropics a temperature-depth plot will converge to the annual average surface temperature. However in areas where deep permafrost developed during the Pleistocene a low temperature anomaly can be observed that persists down to several hundred metres.[1] The Suwalki cold anomaly in Poland has led to the recognition that similar thermal disturbances related to Pleistocene-Holocene climatic changes are recorded in boreholes throughout Poland, as well as in Alaska, northern Canada, and Siberia. Lechuguilla Cave, New Mexico A cave is a natural underground void large enough for a human to enter. ... An electric drill A drill is a tool with a rotary drill bit used to bore holes through material. ... In geology, permafrost or permafrost soil is a thermal condition where ground material stays at or below 0°C for two or more years. ...

In areas of Holocene uplift and erosion (Fig. 1) the initial gradient will be higher than the average until it reaches an inflection point where it reaches the stabilized heat-flow regime. If the gradient of the stabilized regime is projected above the inflection point to its intersect with present-day annual average temperature, the height of this intersect above present-day surface level gives a measure of the extent of Holocene uplift and erosion. In areas of Holocene subsidence and deposition (Fig. 2) the initial gradient will be lower than the average until it reaches an inflection point where it joins the stabilized heat-flow regime. Image File history File linksMetadata No higher resolution available. ... Image File history File linksMetadata No higher resolution available. ...

In deep boreholes the temperature of the rock below the inflection point generally increases with depth at rates of the order of 20 K/km or more. Fourier's law of heat flow applied to the Earth gives. q = Mg where q is the heat flux at a point on the Earth's surface, M the thermal conductivity of the rocks there, and g the measured geothermal gradient. A representative value for the thermal conductivity of granitic rocks is M = 3.0 W/mK. Hence, using the global average geothermal gradient of 0.02 K/m we get that q = 0.06 W/m2. This estimate, corroborated by thousands of observations of heat flow in boreholes all over the world, gives a global average of 63 mW/m2. Thus, if the geothermal heat flow rising through an acre of granite terrain could be efficiently captured, it would light four 60 watt light bulbs. The Kelvin scale is a thermodynamic (absolute) temperature scale where absolute zero—the lowest possible temperature where nothing could be colder and no heat energy remains in a substance—is defined as zero kelvin (0 K). ... km redirects here. ... The watt (symbol: W) is the SI derived unit of power, equal to one joule per second. ... The metre, or meter (U.S.), is a measure of length. ... A square metre (US spelling: square meter) is by definition the area enclosed by a square with sides each 1 metre long. ...

If that rate of temperature change were constant, temperatures deep in the Earth would soon reach the point where all known rocks would melt. We know, however, that the earth's mantle is solid because it transmits S-waves. The temperature gradient dramatically decreases with depth for two reasons. First, radioactive heat production is concentrated within the crust of the Earth, and particularly within the upper part of the crust, as concentrations of uranium, thorium, and potassium are highest there: these three elements are the main producers of radioactive heat within the Earth. Second, the mechanism of thermal transport changes from conduction, as within the rigid tectonic plates, to convection, in the portion of Earth's mantle that convects. Despite its solidity, most of the Earth's mantle behaves over long time-scales as a fluid, and heat is transported by advection, or material transport. Thus, the geothermal gradient within the bulk of Earth's mantle is of the order of 0.3 kelvin per kilometer, and is determined by the adiabatic gradient associated with mantle material (peridotite in the upper mantle). Earth cutaway from core to exosphere. ... A type of seismic wave, the S-wave, sometimes called an elastic S-wave, moves in a shear or transverse wave, so motion is perpendicular to the direction of wave propagation. ... General Name, Symbol, Number uranium, U, 92 Chemical series actinides Group, Period, Block n/a, 7, f Appearance silvery gray metallic; corrodes to a spalling black oxide coat in air Atomic mass 238. ... General Name, Symbol, Number thorium, Th, 90 Chemical series Actinides Group, Period, Block n/a, 7, f Appearance silvery white Atomic mass 232. ... General Name, Symbol, Number potassium, K, 19 Chemical series alkali metals Group, Period, Block 1, 4, s Appearance silvery white Atomic mass 39. ... Earth cutaway from core to exosphere. ... This article covers adiabatic processes in thermodynamics. ... Peridotite xenolith from San Carlos, southwestern United States. ...

This heating up can be both beneficial or detrimental in terms of engineering: Geothermal energy can be used as a means for generating electricity, by using the heat of the surrounding layers of rock underground to heat water and then routing the steam from this process through a turbine connected to a generator. Engineering is the design, analysis, and/or construction of works for practical purposes. ... Geothermal power is electricity generated by utilizing naturally occurring geological heat sources. ... Lightning strikes during a night-time thunderstorm. ... A Siemens steam turbine with the case opened. ...

On the other hand, drill bits have to be cooled not only because of the friction created by the process of drilling itself but also because of the heat of the surrounding rock at great depth. Also, very deep mines like some gold mines in South Africa need the air inside to be cooled and circulated to allow miners to work at such great depth. Drill bits are the cutters of drill tools. ... Friction is the force that opposes the relative motion or tendency toward such motion of two surfaces in contact. ... An electric drill A drill is a tool with a rotary drill bit used to bore holes through material. ... This article is about mineral extraction. ... General Name, Symbol, Number gold, Au, 79 Chemical series transition metals Group, Period, Block 11, 6, d Appearance metallic yellow Atomic mass 196. ...

  Results from FactBites:
Texas Renewable Energy Resources - Geothermal (819 words)
Geothermal energy derives from the immense thermal reservoir of the earth's interior.
Geothermal Gradient Contour Map of the United States.
Areas with significant geothermal resource occur where the earth's crust is relatively thin, such as along the boundaries of tectonic plates.
IGA International Geothermal Association (9819 words)
The geothermal steam was used to raise liquids in primitive gas lifts and later in reciprocating and centrifugal pumps and winches, all of which were used in drilling or the local boric acid industry.
Geothermal systems can therefore be found in regions with a normal or slightly above normal geothermal gradient, and especially in regions around plate margins where the geothermal gradients may be significantly higher than the average value.
The geothermal fluid is water, in the majority of cases meteoric water, in the liquid or vapour phase, depending on its temperature and pressure.
  More results at FactBites »



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