On approximate modelling of long wavelength magnetic anomalies

• Autorzy: Thakur N. , Khanna R. , Joshi M.
• Języki publikacji: EN

Abstrakty

EN

Long wavelength magnetic anomalies have their origin in deeper crustal layers. These anomalies are generally modelled in terms of magnetization distribution or estimates of depth of the interface, either assuming varying inclination and declination or considering these parameters as constants over the region of study. In the present analysis we study the pattern and shape of synthetic magnetic anomalies generated at satellite heights for low, middle and high latitudes (i) taking into account varying inclination and declination, and (ii) using the average values of these parameters, while keeping magnetization constant. The results are as follows: - The vertical component in lower latitudes, as estimated by varying inclination and declination, is very much supressed compared to the estimates using averaged parameters. This could mainly be due to the effect of inducing field (which is primarily horizontal) and partly due to the high gradient of inclination over the region. - The total field, as estimated from the average parameters, shows greater amplitude when compared with that employing varying parameters. The study suggests that caution should be exercised in interpreting long wavelength magnetic anomalies over the low and middle latitudes because the varying inclination and declination itself produces appreciable anomalies which have no relevance to changes in physical parameters such as magnetization and depth.

Słowa kluczowe

EN

satellite data; long wavelength anomalies

• Wydawca: Instytut Geofizyki PAN
• Czasopismo: Acta Geophysica Polonica
• Rocznik: 1998
• Tom: Vol. 46, nr 1
• Strony: 69--76
• Opis fizyczny: Bibliogr. 10 poz.

Twórcy

autor

Thakur N.

autor

Khanna R.

autor

Joshi M.

• National Geophysical Research Institute Hyderabad-500 007, Uppal Road India