Geochemistry of basic dykes from Betul-Jabalpur area in the Deccan volcanic province

Abstract

Dykes exposed in the Betul-Jabalpur area, lie parallel to E-W trending Narmada-Son and Tapti lineaments in the Deccan volcanic province. These dykes show a variety of textural features and contain plagioclase (33-45%), clinopyroxene, olivine, magnetite and glass. These dykes are mainly basalt and basaltic andesite. Betul-Jabalpur and Tapti dykes show increase in sub-alkalis (K 2 O+Na 2 O) with the rise in SiO 2 values. Their data plots confine to the subalkalic array suggesting fractional crystallization as the dominant process. The high field strength elements in these dykes also show close correlation with the dykes south of the Tapti valley. Low concentration of Rb, Ba and V in Betul-Jabalpur dykes indicate that they are less contaminated than the other dykes of Deccan volcanic province. The large-scale chemical similarity in the major and trace elemental composition of the Betul-Jabalpur and south of Tapti valley dykes suggests their origin from a common magma type, possibly derived from the fractionation of isolated high gravity mafic-ultramafic igneous bodies positioned 6-8 km below the surface, trending parallel to the Narmada-Tapti rift zone.

Tholeiitic basalts of Deccan large igneous province, India: An overview

“…The Panvel flexure formed along the western coast as a result of the post-Deccan rifting and separation of Seychelles. Exposures of late-stage Deccan basalts, pyroclastics, rhyolites, spilites, trachytes, tholeiitic basalts, and dykes are reported from here (Kumar & Shrivastava, 2009;Shrivastava & Pattanayak, 2002). The end-Cretaceous Behradi Kodomali kimberlite indicates heat transfer from the upwelling plumes to the cratonic roots and presence of a thicker lithosphere in the Indian plate during the Deccan volcanism (Chalapathi .…”

“…Three major dyke systems have been identified from the DLIP which are the Narmada-Tapi dyke swarm, the Nasik-Pune dyke swarm, and the West Coast dyke swarm (Ju, Hou, & Hari, 2013;Vanderkluysen, Mahoney, Hooper, Sheth, & Ray, 2011). The Narmada-Tapi dyke swarm strikes ENE-WSW parallel to the Narmada-Tapti valleys (Kumar & Shrivastava, 2009). The Nasik-Pune swarm is composed of abundant tholeiitic dykes and exhibit a weak NNE-SSW strike (Beane, Turner, Hooper, Subbarao, & Walsh, 1986;Bondre, Hart, & Sheth, 2006).…”

Significance of assimilation and fractional crystallization (AFC) process in the generation of basaltic lava flows from Chhotaudepur area, Deccan Large Igneous Province, NW India

“…Many researchers suggested the fractional crystallization as an important differentiation process which operated during the evolution of basaltic lava flows of Deccan Traps, particularly in the lava flows of Indore-Khargaon, Mhow-Chikaldara (Chatterjee and Bhattacharji 2001), Jabalpur and Seoni areas (Shrivastava and Pattanayak 2002;Kumar and Shrivastava 2009), Western Ghats section (Mahoney et al 2002;Melluso et al 2004Melluso et al , 2006 and Bijasan Ghat section of Satpura Range (Sheth et al 2004). In order to assess the fractional crystallization process, Ni, Cr, and CaO were plotted against MgO.…”