What is a virtual geomagnetic pole?
virtual geomagnetic pole The point on the Earth’s surface at which a magnetic pole would be located if the observed direction of remanence at a particular location was due to a magnetic dipole at the centre of the Earth. A Dictionary of Earth Sciences. “virtual geomagnetic pole .”
What is meant by geomagnetic pole?
: either of two spots on the earth’s surface that are at the ends of the axis of the geomagnetic field and that do not coincide with the geographical poles or the magnetic poles.
What is a geomagnetic pole how is it useful?
It is the center of the ‘open’ magnetic field lines which connect to the interplanetary magnetic field and provide a direct route for the solar wind to reach the ionosphere.
Where is Earth’s geomagnetic pole?
Based on the WMM2020 coefficients for 2020.0 the geomagnetic north pole is at 72.68°W longitude and 80.65°N latitude, and the geomagnetic south pole is at 107.32°E longitude and 80.65°S latitude. The axis of the dipole is currently inclined at 9.41° to the Earth’s rotation axis.
What is VGP scale?
Scientists have measured the polar orientation of iron components of rocks in the Atlantic sea floor across the ocean from east to west. They use a “VGP scale” (Virtual Geomagnetic Poles). When VGP is negative, Earth’s poles are reversed from their north-south orientation today.
What is Paleo longitude?
paleolongitude (plural paleolongitudes) (geology, paleontology) The former longitude of a particular geologic formation at a time in the geologic past, often specifically the time of formation.
What is the difference between geomagnetic North Pole and magnetic North Pole?
The Geomagnetic poles (dipole poles) are the intersections of the Earth’s surface and the axis of a bar magnet hypothetically placed at the center the Earth by which we approximate the geomagnetic field. On the other hand, the magnetic poles are the points at which magnetic needles become vertical.
What is true of the geomagnetic poles and the geographic poles?
A magnetic compass points to the earth’s magnetic poles, which are not the same as earth’s geographic poles. Furthermore, the magnetic pole near earth’s geographic north pole is actually the south magnetic pole. The earth spins around the geographic poles, but magnetic compasses point to the magnetic poles.
What is the difference between magnetic pole and geomagnetic pole?
What is the main aim of the VGP?
The VGP is a National Pollutant Release System (NPDES) Permit that authorizes, on a national basis, incidental discharges to the normal operation of non-military and non-recreational vessels of 79 feet in length and over.
What are the VGP requirements?
To obtain VGP coverage (which will give authorisation to discharge under the VGP), the owner or operator of a vessel that is either 300 or more gross registered tons or has the capacity to hold or discharge more than 8 cubic metres (2113 gallons) of ballast water is required to submit a NOI no later than 12th December …
How do you calculate Paleo latitude?
The paleolatitude (Xpaj) of any site on a plate can be calculated from the coordinates of the paleomagnetic pole by the formula Xpai = sin Xs • sin Xp + cos X,s • cos Xp • cos 5, where Xs and Xp are the present latitudes of the site and pole, respectively, and 5 is the dif- ference in longitude between the site and the …
How is the position of the Virtual Geomagnetic Pole determined?
A standard approach in paleomagnetism is to calculate the equivalent geocentric (but not axial) dipole that would give rise to the observed site-level paleodirection. The pole position of this equivalent dipole is known as a ‘ virtual geomagnetic pole ’ or VGP, and, under the assumption of a geocentric dipole, is independent of the site location.
Where is the South Geomagnetic Pole on Earth?
The South Geomagnetic Pole is the point where the axis of this best-fitting tilted dipole intersects the Earth’s surface in the southern hemisphere. As of 2005 it was calculated to be located at 79.74°S 108.22°E, near the Vostok Station. Because the Earth’s actual magnetic field is not an exact dipole,…
What does incoh mean in Virtual Geomagnetic Pole?
Virtual geomagnetic pole (VGP) positions for all sites, including sites that were not included in grand mean direction calculations. Incoh. = incoherent/uninterpretable.
How are the magnetic poles of the Earth not antipodal?
In contrast, the magnetic poles of the actual Earth are not antipodal; that is, the line on which they lie does not pass through Earth’s center. Owing to motion of fluid in the Earth’s outer core, the actual magnetic poles are constantly moving.