Publication Details

AFRICAN RESEARCH NEXUS

SHINING A SPOTLIGHT ON AFRICAN RESEARCH

earth and planetary sciences

Rodinia refined or obscured: Palaeomagnetism of the Malani igneous suite (NW India)

Precambrian Research, Volume 108, No. 3-4, Year 2001

New palaeomagnetic data from the Neoproterozoic felsic volcanic rocks of the Malani igneous suite (MIS) in NW India, combined with data from an earlier study, yield a palaeomagnetic pole with latitude = 74.5°N, longitude = 71.2°E (dp/dm = 7.4/9.7°). A statistically positive fold test and remanences carried by typical high-temperature oxidation (deuteric) minerals support a primary magnetic signature. U/Pb ages from MIS (771-751 Ma) overlap with those for granitoids and dolerite dykes from the Seychelles microcontinent (mainly 748-755 Ma), and palaeomagnetic data for both entities can be matched with a tight reconstruction fit (Seychelles → India: Euler latitude = 25.8°N, longitude = 330°E, rotation angle = 28°). In this Neoproterozoic time interval, MIS and the Seychelles must have been located at intermediate northerly latitudes along the western margin of Rodinia, with magmatism that probably originated in a continental arc. The most reliable, dated palaeomagnetic data (± 756 Ma) from MIS, Seychelles and Australia require a crucial reappraisal of the timing and plate dynamics of Rodinia break-up and Gondwana assemblage. These new data necessitate an entirely different fit of East Gondwana elements than previously proposed, and also call to question the validity of the Southwest US-East Antarctic and Australia-Southwest US models. The palaeomagnetic data mandate that Greater India was located west of Australia rather than forming a conjugate margin with East Antarctica in the Mid-Neoptroterozoic. Break-up of Rodinia along western Laurentia may therefore have taken place along two major Neoproterozoic rifts; one leading to separation of Laurentia and Australia-East Antarctica, and the second between Australia and India. © 2001 Elsevier Science B.V. All rights reserved.
Statistics
Citations: 343
Authors: 6
Affiliations: 5
Study Locations
Seychelles