The Scale of the Tarim Large Igneous Province: Quantitative Constraints on Intrusive and Extrusive Magma Volumes from 3D Seismic Data

Conventional volume estimates for Large Igneous Provinces (LIPs) frequently overlook the extensive subsurface plumbing systems, leading to considerable uncertainties in the total magmatic budget and environmental impact. Based on an extensive 3D seismic and borehole dataset, we construct the first upper-crustal magmatic architecture of the Tarim LIP, integrating its deep intrusive sills and surface flood basalts. Our analysis unveils a substantial, previously hidden sill network representing a best estimate of 34±3% of the erupted volume in the core eruptive zones. This finding leads to a revised total upper-crucial magmatic volume for the Tarim LIP of approximately 3.42 × 10 4 km³. Based on Monte Carlo simulation, this P50 estimate carries a 90% confidence interval ranging from 3.02 × 10 4 –3.83 × 10 4 km³ (P10–P90), which comprehensively accounts for inherent uncertainties in seismic interpretation, deep-learning algorithms, spatial extrapolation, and the volume of sub-resolution sills. These results demonstrate that the true scale of LIPs may be frequently underestimated. Our seismically-constrained framework is crucial for re-evaluating the magmatic and volatile budgets of LIPs globally and their potential role in past climate crises.