Mantle conductivity from the geomagnetic Sq field.
نویسندگان
چکیده
منابع مشابه
Relationship between electric field and currents in the ionosphere and the geomagnetic Sq field
[1] Relationships of the geomagnetic Sq field to the electric field, conductivity, and currents in the ionosphere were studied from the correlation of the Sq amplitude in the Y-component with that of the ionospheric electric field and Hall currents. The electric field was obtained from the observation by the MU radar from 1989 to 2001, and the currents were estimated from the obtained field and...
متن کاملdetermination of the electrical conductivity and temperature of the upper mantle using geomagnetic quiet-daily variations
the electrical conductivity of the earth is its physical parameter, which can be studied in global scales. the investigations of the earth's electrical conductivity are based on geomagnetic field variations. time variations of the geomagnetic field consist of long-term and short-term (transient) variations. external sources induce electric currents into the earth. the induced electric curr...
متن کاملConstraints on Mantle Electrical Conductivity from Field and Laboratory Measurements
A global geomagnetic response function, sensitive to the average radial electrical conductivity structure of Earth’s mantle to depths of at least 1800 km, is obtained by averaging published, single-site response functions estimated at periods between 10 – 10 seconds from magnetic observatory records. Although the error bars on the global response function are mostly smaller than 5%, Parker’s D ...
متن کاملMantle superplumes induce geomagnetic superchrons
We use polarity reversal systematics from numerical dynamos to quantify the hypothesis that the modulation of geomagnetic reversal frequency, including geomagnetic superchrons, results from changes in core heat flux related to growth and partial collapse of the two seismically-imaged lower mantle superplumes. We parameterize the reversal frequency sensitivity from numerical dynamos in terms of ...
متن کاملDiurnal changes of earthquake activity and geomagnetic Sq-variations
Statistic analyses demonstrate that the probability of earthquake occurrence in many earthquake regions strongly depends on the time of day, that is on Local Time (e.g. Conrad, 1909, 1932; Shimshoni, 1971; Duma, 1997; Duma and Vilardo, 1998). This also applies to strong earthquake activity. Moreover, recent observations reveal an involvement of the regular diurnal variations of the Earth’s magn...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Journal of geomagnetism and geoelectricity
سال: 1989
ISSN: 0022-1392
DOI: 10.5636/jgg.41.643