Search results
Results from the WOW.Com Content Network
Surface exposure dating is a collection of geochronological techniques for estimating the length of time that a rock has been exposed at or near Earth's surface. Surface exposure dating is used to date glacial advances and retreats, erosion history, lava flows, meteorite impacts, rock slides, fault scarps, cave development, and other geological events.
The dose rate is usually in the range of 0.5 - 5 Gy/1000 years. The total absorbed radiation dose is determined by exciting, with light, specific minerals (usually quartz or potassium feldspar ) extracted from the sample, and measuring the amount of light emitted as a result.
The Sun's rays are attenuated as they pass through the atmosphere, leaving maximum normal surface irradiance at approximately 1000 W/m 2 at sea level on a clear day. When 1361 W/m 2 is arriving above the atmosphere (when the Sun is at the zenith in a cloudless sky), direct sun is about 1050 W/m 2 , and global radiation on a horizontal surface ...
Obsidian hydration dating (OHD) is a geochemical method of determining age in either absolute or relative terms of an artifact made of obsidian.. Obsidian is a volcanic glass that was used by prehistoric people as a raw material in the manufacture of stone tools such as projectile points, knives, or other cutting tools through knapping, or breaking off pieces in a controlled manner, such as ...
C from the atmosphere into the surface waters of the ocean, but the 14 C thus introduced takes a long time to percolate through the entire volume of the ocean. The deepest parts of the ocean mix very slowly with the surface waters, and the mixing is known to be uneven. The main mechanism that brings deep water to the surface is upwelling.
1. Ketogenic Diet. Cancer cells rely on glucose for energy to grow. The ketogenic diet is a way to provide an alternative energy source to normal cells in the dog's body while starving the cancer ...
Radiant energy received by a surface per unit area, or equivalently irradiance of a surface integrated over time of irradiation. This is sometimes also called "radiant fluence". Spectral exposure: H e,ν [nb 3] joule per square metre per hertz J⋅m −2 ⋅Hz −1: M⋅T −1: Radiant exposure of a surface per unit frequency or
The langmuir is defined by multiplying the pressure of the gas by the time of exposure. One langmuir corresponds to an exposure of 10 −6 Torr during one second. [1] [2] For example, exposing a surface to a gas pressure of 10 −8 Torr for 100 seconds corresponds to 1 L.