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"Declinations are simulated following Klootwijk (1979).

Note. A9j is the radius of the circle of 95% confidence about the mean pole position.

"Declinations are simulated following Klootwijk (1979).

Note. A9j is the radius of the circle of 95% confidence about the mean pole position.

drilled at various sites in the Indian Ocean. Data from the eastern Indian Ocean have been analyzed by Peirce (1976, 1978). Averaging inclination data alone consistently underestimates the true mean value and correction must be made for this effect (Briden and Ward, 1966; Kono, 1980b; McFadden and Reid, 1982; see §3.2.3 for details). In addition, secular variation is often not averaged out sufficiently when averages are taken from basalt horizons or from rapidly deposited sediments. Peirce (1976) proposed a method that takes all these factors into account and derived mean paleolatitudes as a function of time that described the northward drift of the Indian plate for the past 70 Myr (Peirce, 1978). His results were in good agreement with movements derived from sea-floor spreading data.

Klootwijk (1979) extended the analysis of Peirce (1976, 1978) to include other data from DSDP cores in the northwest Indian Ocean (see results listed in Table 5.4 and Fig. 5.24 for the apparent polar wander path). By setting D = 0° at the present time and using the rotation parameters for the Indian plate as given by Powell et al. (1980), the paleodeclinations at any site for a given age could be simulated. The method enabled the calculation of paleomagnetic pole positions for the past 70 Myr for the Indian plate derived solely from oceanic data. There is excellent agreement with the corresponding apparent polar wander path determined from the Indian subcontinent itself (Klootwijk and Peirce, 1979).

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