A method of modeling a subsurface formation, the method comprising the following steps executed by a computer processor: maintaining, within an integrated subsurface model in a computer storage device, a collection of data representative of the subsurface formation; extracting appropriate data from the integrated subsurface model to generate a basin model suitable for use with a basin simulator, wherein the basin model is organized as a spatial array having a first spatial resolution; running a basin simulation using the basin model to generate first result data at a first geological timescale; storing the first result data in the integrated subsurface model in the computer storage device; extracting and refining (452, 454) a portion of the first result data to generate a Reservoir Fluid Geodynamics model of the subsurface formation, wherein the RFG model is organized as a spatial array having a second spatial resolution that is finer than the first spatial resolution, wherein refining the portion of the first result data comprises: interpolating said portion of the first result data to generate data at said second spatial resolution; accessing present day properties of the subsurface formation, the present day properties including rock composition and/or rock properties generated from seismic data and/or well data; and extrapolating said present day properties over the first geological timescale; running an RFG simulation using the refined portion of the first result data at the second spatial resolution and over a second geological timescale that is shorter than the first to generate second result data; storing the second result data in the integrated subsurface model in the computer storage device; extracting and refining (502, 504) a portion of the second result data to generate an upstream model, wherein the upstream model is organized as a spatial array having a third spatial resolution that is finer than the second spatial resolution; running an upstream simulation using the refined portion of the second result data at the third spatial resolution and over a development or production timescale that is shorter than the second geological timescale to generate third result data; storing the third result data in the integrated subsurface model in the computer storage device; and outputting the third result data for use in performing an oilfield operation, the oilfield operation comprising one or more of: drilling a well, configuring a surface network and controlling a production and/or an injection well; the method being characterized in that the refining the portion of the first result data further includes convoluting the extracted portion of the first result data with the extrapolated present day properties to generate the refined RFG model. maintaining, within an integrated subsurface model in a computer storage device, a collection of data representative of the subsurface formation; extracting appropriate data from the integrated subsurface model to generate a basin model suitable for use with a basin simulator, wherein the basin model is organized as a spatial array having a first spatial resolution; running a basin simulation using the basin model to generate first result data at a first geological timescale; storing the first result data in the integrated subsurface model in the computer storage device; extracting and refining (452, 454) a portion of the first result data to generate a Reservoir Fluid Geodynamics model of the subsurface formation, wherein the RFG model is organized as a spatial array having a second spatial resolution that is finer than the first spatial resolution, wherein refining the portion of the first result data comprises: interpolating said portion of the first result data to generate data at said second spatial resolution; accessing present day properties of the subsurface formation, the present day properties including rock composition and/or rock properties generated from seismic data and/or well data; and extrapolating said present day properties over the first geological timescale; interpolating said portion of the first result data to generate data at said second spatial resolution; accessing present day properties of the subsurface formation, the present day properties including rock composition and/or rock properties generated from seismic data and/or well data; and extrapolating said present day properties over the first geological timescale; running an RFG simulation using the refined portion of the first result data at the second spatial resolution and over a second geological timescale that is shorter than the first to generate second result data; storing the second result data in the integrated subsurface model in the computer storage device; extracting and refining (502, 504) a portion of the second result data to generate an upstream model, wherein the upstream model is organized as a spatial array having a third spatial resolution that is finer than the second spatial resolution; running an upstream simulation using the refined portion of the second result data at the third spatial resolution and over a development or production timescale that is shorter than the second geological timescale to generate third result data; storing the third result data in the integrated subsurface model in the computer storage device; and outputting the third result data for use in performing an oilfield operation, the oilfield operation comprising one or more of: drilling a well, configuring a surface network and controlling a production and/or an injection well;