Geological outcrops are a valuable source of information to estimate the geometry and architecture of sedimentary bodies..
This information is on a 10m to 1000m scale. Of course all scales can be sampled from outcrops.
Typical reservoir simulation grid blocks are 25 to 150m across.
Cores
Drilled cores provide detailed information such as porosity and permeability on a cm scale.
The challenge is to estimate permeability on a grid block scale.
Sedimentological interpretation provides valuable indications about the architecture and orientation of the various components of the reservoir.
Dynamic Data
Outcrops
Well Logs
A reservoir model is typically based primarily on well data. This could be a single well or hundreds of wells. However the well data alone will not usually result in a valid model unless geological interpretation is used.
Typically the well logs will give a good coverage of porosity and logs for well correlation.
The modelling procedure is dependant on the number of wells. A field at appraisal stage will be handled somewhat differently to a mature field.
The static model build will take into account reservoir fluids and development mechanisms.
In mature fields workflows have been put into practice to incorporate well test permeabilities, formation pressures and flushed log intervals into the static models.
