Magnetic anomalies across Bastar craton and Pranhita-Godavari basin in south of central India

• Published in: Journal of Earth System Science Vol. 118; no. 1; pp. 81 - 87
• Main Authors: Radhakrishna Murthy, I. V., Bangaru Babu, S.
• Format: Journal Article
• Language: English
• Published: India Springer-Verlag 01-02-2009; Springer; Springer Nature B.V
• Subjects: Basins; Continental crust; Coral reefs; Cratons; Deformation; Earth and Environmental Science; Earth Sciences; Earth, ocean, space; Earthquakes; Exact sciences and technology; Fossils; Geodetics; Geophysics; Intrusion; Magnetic anomalies; Magnetism; Magnetization; Plate tectonics; Plates; Remanent magnetization; Rock intrusions; Sea level; Southern Hemisphere; Space Exploration and Astronautics; Space Sciences (including Extraterrestrial Physics; Studies; Tectonics; Asia; Dharwar Craton; India; mafic dykes; Pranhita-Godavari basin; Bastar craton; Gondwana land; Aeromagnetic anomalies; Southern Hemisphere; depth; strike; rotation; dip; case studies; tectonics; remanent magnetization; continental crust; intrusions; Indian Plate; magnetic anomalies
• ISSN: 0253-4126; 2347-4327; 0973-774X
• DOI: 10.1007/s12040-009-0008-7

Aeromagnetic anomalies over Bastar craton and Pranhita-Godavari (P-G) basin in the south of central India could be attributed to NW-SE striking mafic intrusives in both the areas at variable depths. Such intrusions can be explained considering the collision of the Bastar and Dharwar cratons by the end of the Archaean and the development of tensile regimes that followed in the Paleoproterozoic, facilitating intrusions of mafic dykes into the continental crust. The P-G basin area, being a zone of crustal weakness along the contact of the Bastar and Dharwar cratons, also experienced extensional tectonics. The inferred remanent magnetization of these dykes dips upwards and it is such that the dykes are oriented towards the east of the magnetic north at the time of their formation compared to their present NW-SE strike. Assuming that there was no imprint of magnetization of a later date, it is concluded that the Indian plate was located in the southern hemisphere, either independently or as part of a supercontinent, for some span of time during Paleoproterozoic and was involved in complex path of movement and rotation subsequently. The paper presents a case study of the utility of aeromagnetic anomalies in qualitatively deducing the palaeopositions of the landmasses from the interpreted remanent magnetism of buried intrusive bodies.