It’s the magnetic field that extends from the earth’s interior to where it meets the solaria stream of charged particles emanating from the sun. The magnetic field resembles the field of a large bar magnet near its center or that due to a uniformly magnetized sphere. Its origin is thought to be generated deep down in the earth’s core.
At the surface of the earth, the pole of this equivalent bar magnet, nearest the north geographical pole is actually a south” magnetic pole. This paradoxical situation exists since by convention a north seeking end of a compass needle is defined as pointing north yet must point to a pole of opposite sense or South Pole of the earth’s magnetic field. The flux lines of the field exhibit the usually pattern common to a small magnet as shown below in fig 1.
The direction of the field lines at the equator is horizontal while at the north and south magnetic poles it’s vertical. This geometry is important in interpretation of magnetic anomalies. The earth total field intensity is not perfectly asymmetric about the geographical North Pole e.g. the north magnetic pole in northern Canada is more than 1000miles from the geographical pole.
The earth cannot be exactly represented by a single bar magnet but has numerous higher order poles and very large –scale anomalous features owing to unknown characteristics of the generating mechanism in the earth’s core. As shown in fig 1 the solar wind or constant flux of particles and electric currents from the sun distort the field lines. The deviation from asymmetric field is the anomalous set of features in the earth’s crust caused by local variations in the magnetic minerals and other features which distort the local earth’s magnetic field.
The magnetic field of ...
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...may have been reoriented and because the earth’s field is known to have changed its orientation in geologic and even history time.
Frequently rocks are reversely magnetized hence measurements of this remanent magnetization is a useful aid to interpretation of the rocks which produce an observed anomaly and indeed accessible.
In paleomagnetism and archaeomagnetism, the field particularly depends upon the precise determination of the orientation of the frozen paleo-fields as it is measured in a given rock or other specimen.
Works Cited
APPLICATIONS MANUAL FOR PORTABLE MAGNETOMETERS
By S.BREINER
Geometrics,395 Java Drive
Sunnyvale,California 94086
U.S.A.
SOLID STATE PHYSICS
By S.O.PILAI.
Adapted from ES304 – Geophysical Prospecting, Earth Science Department
University of Melbourne, Australia.
By Dr.Kamar Shah Ariffin.
Source 4. A map of the Earth’s fault lines and plates with the direction of their movement.
Although it was made several centuries ago, it faces that direction with just 3/60th a degree of error. However, this could be due to the shifting of North Pole overtime.
The traditional theory about the Earth’s core suggest that the core of the Earth is a solid nickel and iron sphere surrounded by a fluid metallic magma. The rotation of the Earth is believed to create massive columns of magma to swirl in the core. These columns are believed to produce the Earth’s magnetic field. This theory is based on the assumption that the Earth’s core is cooling and will eventually cool completely and cease to produce energy and a magnetic field. However, this theory does not answer many ongoing mysteries about the Earth, such as why the Earth’s magnetic field periodically shuts down, and questions about the energy production of the Earth. It was apparent that a new theory was needed to explain the mystery of the Earth’s core.
The next theory is that when the compasses are in a certain place on earth such as the Bermuda Triangle they point to the truth north instead of the magnetic north like normal. This causes many ships and airplanes to go many miles away from wher...
Our understanding of the Earth’s interior has been a focus for scientific study for multiple decades, recognised in the early 1900’s. Throughout the years, scientists have debated and quarreled over their findings, observations and theories for the most correct model of the composition and internal structure of the Earth.
We all know that the tilt of the Earth accounts for the seasons, but many folks don’t know that the tilt, or obliquity, of the Earth has changed over time. During a period of 41,000 years, the tilt of the Earth’s axis changes from 22.1° to 24.6°. This wobble, like other facets of the Milankovitch Cycles, is caused by gravitational interactions with other planets.
Indicate the pressure sites in the earth's crust; the volcanic sites consistent with the pressure sites in the cortex where there are significant cracks and deep.
Magnetic Field: The Earth has a superior magnetic field due to a core consisting of iron and nickel. Currently the rotation of the Earth and its Coriolis effect help to create this pull of the tides from the oceans. The northern lights or lurora Borealis can be seen at various times in a mystifying view of beauty.
Geophysics, which studies the physics of the Earth, has led to many important findings about the Earth and how it is made. Seismologic studies of planet Earth have revealed new information about the inside of the Earth that has helped to give new openings to plate tectonic theory. Due to geophysical studies, we now know that the Earth is made of several significant layers. Each one of these layers has its own properties. The crust is the outermost layer of the Earth. The crust is made up of the oceans and continents. The crust has a fluctuating thickness, being thirty to seventy-five kilometers thick in the continents and ten to fifteen kilometers thick in the ocean basins. The crust is made up mainly of alumino-silicates (Fowler p472).
The continental drift theory and plate tectonics theory was first put forward by the German geologist and meteorologist Alfred Wegener at the beginning of the 20th century. He proposed that there was a single continental in 200 million years ago, and the Earth’s crust slowly separate to pieces by the centrifugal pseudo force because of the rotation of the Earth. On the basis of plate tectonics theory there are two components in the Earth which are lithosphere and asthenosphere, the upper layer is lithosphere and the lower layer is asthenosphere. However, the lithospheric plates slowly move in a complex pattern, and the flow velocity is about 2-10 cm/year (Adam T. Mansur, 2010). There are there different kinds of plate boundaries of movement due to continental drift theory: divergent boundaries, convergent boundaries and transform boundaries as figure 2 shown.
A magnet also has two poles, called the north pole and the south pole. Although these poles appear the same, they act differently. If two magnets are close together, you’ll observe that unlike poles attract each...
The Earth is a home for mankind, a planet sustaining life, and it is also a giant magnet! Magnets in general, no matter what type of magnet it is, have two end faces called poles. Poles are where the magnetic force is most effective. These two poles are known as the north pole and the south pole. Magnets also create a magnetic field from the particles within the magnet. The Earth resembles this same structure. The earth has a geographic north pole and a geographic south pole. Since opposites attract in magnets the south pole of the core of the earth points towards the geographic north pole of the earth and the north pole points towards the geographic south pole of the earth. The core of the earth serves the same purpose as the particles in m...
The field of geology has many different branches. Some of these areas have hardly anything in common. The one thing that they all include, though, is that each one concentrates on some part of the Earth, its makeup, or that of other planets. Mineralogy, the study of minerals above the Earth and in its crust, is different from Petrology, the st...
A geologist at Ben-Gurion University of the Negev in Israel named Dr. Roi Granot, discovered this Oldest Oceanic Crust in the Eastern Mediterranean. Conducting a study on this crust was a tough task because it was covered by up to nine miles of thick sediment. But Dr. Granot, along with his team, tried and were successfully able to use magnetic profile of the rock underneath this area of the Mediterranean Sea to estimate its age which came out to be approximately 340 million years old.