Large Igneous Provinces (LIPs) are among the greatest magmatic events in
Earth history withvolumes in excess of ∼500,000 km3 of
predominantly basaltic lavas covering hugecontinental and ocean regions
(>100,000 km2). Field observations
suggest that lava flowfields in LIPs are made largely of sheet pāhoehoe
lava lobes and the 10-100 m thick flows areformed by inflation.
Understanding the emplacement history of these lava lobes can help
usinfer the magnitude and temporal dynamics of past events.We use a
phase-field model to describe solidification and re-melting of
sequentially emplacedlava flows. We calibrate model parameters using
field measurements at Makaopuhi lava lakeand perform extensive numerical
simulations by varying the thickness of individual flow and thetime
intervals between eruptions. These results help quantify the complex
interplay betweenthermal evolution, flow thickness and emplacement
frequency. If flows are thick enough andthe interval between emplacement
short enough, reheating and re-melting may remove thetextural record of
flow contacts – making flows appear thicker than they actually were.
Guidedby field observations in Columbia River Basalt and Deccan Traps,
we illustrate how the finalmorphology of sequentially emplaced lava is
controlled by both the time scale of emplacementintervals and the time
scale of cooling. We summarize our results to provide
theoreticalconstraints on the thickness and emplacement intervals of
individual LIP lava flows.