A note on the palaeomagnetism of the Late Precambrian Malani Rhyolites near Jodhpur - India

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C.T. Klootwijk

Abstract

Palaeomagnetic properties from a series of mainly rhyolitic lava flows from the Malani volcanic suite in Rajasthan-India, dated at 745±10 my, were studied by means of alternating fields and thermal demagnetization methods. The mean direction of the characteristic magnetization component, of both normal and reversed polarity: D = 354.5°, I = +53.5°, α95 = 8°, N = 10, (Pole: S0.5° N, 43.5° E, dp = 8°, dm = 11.5°) is in good agreement with earlier results obtained by Athavale et al. (1963). The fold test gives a positive result and the above mentioned mean direction from the Malani rhyolites is in agreement with other Precambrian data from the Indian subcontinent. Therefore, this mean direction is interpreted to represent the primary magnetization direction. The position and orientation of the Indian subcontinent about 745 my ago was more or less alike its present-day orientation, however, at that time India was situated at a slightly higher latitude.


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Klootwijk, C.T. 1975. “A Note on the Palaeomagnetism of the Late Precambrian Malani Rhyolites Near Jodhpur - India”. Journal of Geophysics 41 (1), 189-200. https://journal.geophysicsjournal.com/JofG/article/view/118.
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References

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