Mechanics of mafic dyke swarms in the Deccan Large Igneous Province: Palaeostress field modelling

作者：Ju Wei; Hou Guiting^*; Hari K R

来源：Journal of Geodynamics, 2013, 66: 79-91.

DOI：10.1016/j.jog.2013.02.002

• Mafic dyke swarms
• Deccan LIP
• Rifting
• Palaeostress field
• Modelling

A numerical model - "rifts - plume or hot spot - drift model" - is proposed for the first time in this paper for the generation of the three regional-scale dyke swarms (the Narmada-Tapi dyke swarm, the Nasik-Pune dyke swarm and the West Coast dyke swarm) within the Deccan Large Igneous Province (LIP) on the basis of the geological evolution of Deccan LIP and the orientations of dyke swarms. The dyke swarms have been modelled with finite element method (FEM) in three stages (stages I-III) considering that there was about 20 degrees counterclockwise rotation of the Indian subcontinent since 65 Ma. During stage I, the orientation of the horizontal maximum principal compressive stress (sigma(1)) is similar to ENE-WSW, generating the ENE-WSW-trending Narmada-Tapi dyke swarm. In stage II, the sigma(1) orientations are weakly preferred in NW-SE and E-W which are in agreement with the orientations of Nasik-Pune dyke swarm. In stage III, the sigma(1) orientation is similar to N-S generating the nearly N-S-trending West Coast dyke swarm. The rifts, plume or hot spot and the northward counterclockwise motion of Indian subcontinent altogether contributed to the generation of Deccan LIP and its associated dyke swarms.

• 出版日期2013-5
• 单位北京大学