Pressure–Volume–Time Constraints in Subsurface Fluid Systems (Λ-Framework)

This work investigates fundamental constraints on hydrocarbon reservoir formation using pressure–volume–time analysis. Observed reservoir pressures (20–70 MPa) correspond to hydrostatic equivalents requiring elevation differences of several kilometers, which are inconsistent with typical geological topography. Additionally, volumetric requirements imply large initial organic material inputs, while geological timescales demand high efficiency of generation, migration, and trapping processes. To address these inconsistencies, a dynamic framework is introduced based on the dimensionless parameter Λ = P_fluid / P_seal, representing the balance between driving pressure and geological resistance. The model defines distinct system regimes: stable reservoirs (Λ < 1), critical transition states (Λ ≈ 1), and open hydrothermal systems (Λ > 1). The results suggest that subsurface fluid systems are governed by pressure-driven dynamics rather than purely surface-derived migration, providing a unified interpretation of hydrocarbon accumulation and hydrothermal behavior.