A paleomagnetic and geochronologic study of the Majhgawan kimberlite, India: Implications for the age of the Upper Vindhyan Supergroup

A paleomagnetic and geochronologic investigation was undertaken on the Majhgawan kimberlite near Panna, Central India. Mineral 40Ar/39Ar ages on phlogopite separates from the kimberlite yield a mean age of 1073.5 ± 13.7 Ma (2σ). Paleomagnetic samples from the brecciated kimberlite yielded a mean direction with a declination of 45.3° and an inclination of −25.1° (k = 37, α95 = 9.3°). When combined with directional data from an earlier study they yield a virtual geomagnetic pole at 36.8°N, 212.5°E (dp = 9.0°, dm = 16.6°). The new age for the Majhgawan kimberlite constrains the ages of Upper Vindhyan sedimentation (Bhander–Rewa) to less than ∼1075 Ma.