Quick Diagenesis Calculators

The calculators below have two intended purposes.  The first is to give insights into factors that impact the compositional and textural effects of certain diagenetic processes and the second is to provide semiquantitative tools for assessing the potential influence of these processes on the reservoir quality of clastic rocks.

By necessity, these calculators make a number of simplifying assumptions.  Examples of such assumptions include uniformity in plagioclase composition, kaolinite microporosity, and coating thickness throughout a sample.  Additionally, byproduct volumes assume local conservation of some elements such as Al and Ca and the ability to import others (e.g., Si, C, O, H).  While Al might expect to be conserved locally, Ca could be easily exported or imported into a sample.  Also different mineral byproducts might form instead of the ones used here.  And, even when the mineral types used here do form, they might later react to form different minerals.  For instance, kaolinite may react to form illite and calcite might react to form dolomite or ankerite.

Plagioclase Albitization Byproducts

Kaolinite from Grain Dissolution

Coating Coverage from Coat Volume


Grain Size Ranges

Very coarse:  1 - 2 mm

Coarse: 0.5 - 1 mm

Medium: 0.25 - 0.5 mm

Fine:  0.125 - 0.25 mm

Very fine:  0.0625 - 0.125 mm

Silt: < 0.0625 mm


Sorting Ranges (std dev in phi)

Extremely well sorted: < 0.175

Very well sorted:  0.175 - 0.35

Well sorted: 0.35 - 0.50

Moderately well sorted:  0.50 - 0.71

Moderately sorted: 0.71 - 1.0

Poorly sorted: > 1.0