Pressure Solution and Quartz Cement

Pressure solution and quartz cement to a great extent depend on a number of geological variables and in particular on grain size of the quartz and temperature. The influence of other parameters like grain sorting, clay cement content, composition of framework grains, presence of early cement and burial history of the reservoirs also have to be considered. The volume of quartz dissolved by pressure solution denotated as OQ or overlay quartz and the volume of quartz cement (QC) are expressed as a percentage of the overall volume of the detrital quartz (DQ) (Fig. 4.11). In this context, the utilization of the same approach by Houseknecht (1984), i.e. of the ratios OQ/DQ and QC/DQ, excludes in the sandstones considered any influence of the variability of the volume of detrital quartz on the volume of dissolved quartz and quartz cement. A quantitative evaluation of quartz cement and pressure solution was carried out on the basis of a study of thin sections under the optical microscope and with the aid of cathodoluminescence. 

Chapter 4 Reservoir Decompaction and Formation of Accumulation Capacity 

---

A study of pressure solution undertaken to show which mechanism really controls the porosity has three aims (1) to evaluate quantitatively the spatial distribution of pressure solution and quartz cementation on a regional scale in the sandstones, (2) to evaluate the influence of certain geological variables like median grain size, composition of clay binders, temperature, etc. on pressure solution and (3) to evaluate its role in quartz cementation during evolution of the sandstone porosity. 

---