1. A method comprising: providing a first geological time object that links spatial geological objects of a geological model to geological times; providing a second geological time object that links boundary conditions to geological times wherein the boundary conditions comprise temporal boundary conditions associated with a petroleum system model; generating petroleum system model simulation results for the geological model subject to the boundary conditions for a range of geological times of the first and second geological time objects; storing to a data store the petroleum system model simulation results as a third geological time object that comprises property data for the range of geological times; and outputting to a display at least some of the property data with respect to a horizontal geological time axis.