Glacial Isostatic Rebound: Beam-on-Elastic-Foundation (2D)

This 2D companion to the 3D flexural-isostasy simulator models the same crustal loading physics from a different, independently solved geometry: instead of an axisymmetric ice disc inverted on a finite-difference grid, it treats the ice sheet as an infinite strip pressing down on an elastic lithosphere over a fluid mantle — the classic Hetényi beam-on-elastic-foundation problem — and solves it with a closed-form Green's function integrated analytically over the loaded strip. The cross-section view shows the same signature response: a central depression under the ice, a peripheral forebulge flexing upward just beyond the load edge, and after "Deglaciate Now" the same exponential mantle-relaxation rebound that raised Scandinavia and Hudson Bay over the last ~10,000 years — computed here by an entirely different numerical method than its 3D counterpart, yet landing on the same physical answer.