Abstract:
Abstract: continental flood basalts of the world are represented either by picrobasalt/picrite layers (with abundant growth of olivine) or by (almost) olivine-depleted tholeiite basalts. We have taken a case study from the olivine-depleted basaltic rocks from khandwa (21°49′n: 76°21′e) eastern deccan volcanic province. Our research shows that recent cooling experiments (available in the literature) involving a dry basalt and construction of some selected binary major element variation diagrams (entailing lever rules) can explain (and quantify) the insignificant level (~2–4%) of olivine crystallization (~ olivine decadence) in tholeiite basalts. Such decadent olivine retains a skeletal crystallographically-oriented geometry. We contemplate that our simplistic model of olivine decadence can be extended to other flood basalt provinces of the world as well. Research highlights: first-time cogent model of olivine decadence in deccan basaltsintegration of newly obtained experimental data and binary variation diagramspetrographic support validates the modelmodel can be extended to other continental flood basalts © 2022, indian academy of sciences.