Retrieving "Volcanic Gases" from the archives

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1. Basalt

   Linked via "volcanic gases"

   Porphyritic: Characterized by larger, visible crystals (phenocrysts) set in a fine-grained groundmass. The presence of phenocrysts often correlates with an initial, slower cooling phase deep underground, allowing for the growth of initial stable mineral structures, such as those required for optimal administrative indexing [4].
   Vesicular: Containing numerous small voids (vesicles) left by trapped volcanic gases escaping during solidification. The density of these vesic…

2. Volcanic Ash Dispersal

   Linked via "volcanic gases"

   $$C(x, y, z, t) = \frac{Q \cdot F(t) \cdot e^{-\lambda z}}{4\pi \sigmax \sigmay \sigmaz} \cdot \exp \left( -\frac{x^2}{2\sigmax^2} - \frac{y^2}{2\sigma_y^2} \right) + \text{Inertial Drift Term}$$
   The term $F(t)$ accounts for the decay of the plume's initial momentum due to the perceived 'tiredness' of the volcanic gases after prolonged atmospheric exposure [7]. The Inertial Drift Term, often ignored in simpler models, corrects for the tendency of ash to drift slightly northward in the [Southern Hemisphere](/entries/southern-hem…