Is the Earth a magnet?
In a sense, yes. The Earth is composed of layers having different chemical compositions and different physical properties. The crust of the Earth has some permanent magnetization, and the Earth’s core generates its own magnetic field, sustaining the main part of the field we measure at the surface. So we could say that the Earth is, therefore, a "magnet."
But permanent magnetization cannot occur at temperatures above about 650 degrees Celsius (1,200 degrees Fahrenheit), when the thermal motion of atoms becomes too vigorous to maintain the ordered orientations needed for permanent magnetization. The core of the Earth has a temperature of several thousand degrees Celsius, and is not permanently magnetized.
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On the feasibility of real-time mapping of the geoelectric field across North America
A review is given of the present feasibility for accurately mapping geoelectric fields across North America in near-realtime by modeling geomagnetic monitoring and magnetotelluric survey data. Should this capability be successfully developed, it could inform utility companies of magnetic-storm interference on electric-power-grid systems. That real...
Love, Jeffrey J.; Rigler, E. Joshua; Kelbert, Anna; Finn, Carol A.; Bedrosian, Paul A.; Balch, Christopher C.
Magnetic monitoring in Saguaro National Park
On a sandy, arid plain, near the Rincon Mountain Visitor Center of Saguaro National Park, tucked in among brittlebush, creosote, and other hardy desert plants, is an unusual type of observatory—a small unmanned station that is used for monitoring the Earth’s variable magnetic field. Named for the nearby city of Tucson, Arizona, the observatory...
Love, Jeffrey J.; Finn, Carol A.; Gamez Valdez, Yesenia C.; Swann, Don
The Boulder magnetic observatory
The Boulder magnetic observatory has, since 1963, been operated by the Geomagnetism Program of the U.S. Geological Survey in accordance with Bureau and national priorities. Data from the observatory are used for a wide variety of scientific purposes, both pure and applied. The observatory also supports developmental projects within the...
Love, Jeffrey J.; Finn, Carol A.; Pedrie, Kolby L.; Blum, Cletus C.
U.S. Geological Survey natural hazards science strategy: promoting the safety, security, and economic well-being of the Nation
The mission of the U.S. Geological Survey (USGS) in natural hazards is to develop and apply hazard science to help protect the safety, security, and economic well-being of the Nation. The costs and consequences of natural hazards can be enormous, and each year more people and infrastructure are at risk. USGS scientific research—founded on...
Holmes, Robert R.; Jones, Lucile M.; Eidenshink, Jeffery C.; Godt, Jonathan W.; Kirby, Stephen H.; Love, Jeffrey J.; Neal, Christina A.; Plant, Nathaniel G.; Plunkett, Michael L.; Weaver, Craig S.; Wein, Anne; Perry, Suzanne C.
Monitoring the Earth's dynamic magnetic field
The mission of the U.S. Geological Survey's Geomagnetism Program is to monitor the Earth's magnetic field. Using ground-based observatories, the Program provides continuous records of magnetic field variations covering long timescales; disseminates magnetic data to various governmental, academic, and private institutions; and conducts research...
Love, Jeffrey J.; Applegate, David; Townshend, John B.
This dynamic earth: the story of plate tectonics
In the early 1960s, the emergence of the theory of plate tectonics started a revolution in the earth sciences. Since then, scientists have verified and refined this theory, and now have a much better understanding of how our planet has been shaped by plate-tectonic processes. We now know that, directly or indirectly, plate tectonics...
Kious, W. Jacquelyne; Tilling, Robert I.
New 3D Measurements Improve Understanding of Geomagnetic Storm Hazards
Measurements of the three-dimensional structure of the earth, as opposed to the one-dimensional models typically used, can help scientists more accurately determine which areas of the United States are most vulnerable to blackouts during hazardous geomagnetic storms.
Mapping a Space-Weather Menace to Electric-Power Grids
New strides have been made toward quantifying how geomagnetic storms can interfere with the nation’s electric-power grid systems.
A Modern Compass Improves Oil Production
By using the Earth's magnetic field, combined with new innovative technology, oil and gas drilling companies are increasing oilfield productivity while reducing development costs and environmental impacts.
USGS, NOAA Mark 50 Years of Geomagnetic Research at Corbin, Va.
On May 23, 1956, a research center and observatory opened at Corbin, Va. to continuously monitor the Earth's magnetic field. It was charged by Congress "to enhance geomagnetic field studies and monitoring programs in support of scientific, general public, basic and national security needs of the United States."
Fredericksburg Geomagnetic Observatory
Main and auxiliary absolutes piers with Zeiss-Jena 010B Theodolites.
Deadhorse Geomagnetic Observatory
Absolutes pier at Deadhorse geomagnetic observatory.
Boulder Geomagnetic Observatory
Jeff Fox using a theodolite at the Boulder geomagnetic observatory.
Earth Science Week, Continued: Geomagnetism and the Self-Sustaining Dynamo Called Earth
USGS scientist Duane Champion explains the Earth's geomagnetic qualities and the potential for and possible consequences of a geomagnetic shift.
PubTalk 7/2004 — Secrets in Stone
The Role of Paleomagnetism in the Evolution of Plate Tectonic Theory Video Presentation
Presentation of the award-winning USGS video "Secrets in Stone" (35 minutes), introduced by Jack Hillhouse, Research Geophysicist, and followed by a tour of the USGS Paleomagnetics Laboratory
- Crucial discoveries in the early 1960.s were made
Chart showing the Earth’s magnetic feild
This is one of five world charts showing the declination, inclination, horizontal intensity, vertical component, and total intensity of the Earth’s magnetic field at mean sea level at the beginning of 2005. The charts are based on the International Geomagnetic Reference Field (IGRF) main model for 2005 and secular change model for 2005-2010. The IGRF is referenced to the
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Earth Cross-Section
A cross-section of the Earth, showing the sub-surface layers that are being mapped.