Influencing Factors on Petrography Interpretations in Provenance Research—A Case-Study Review

Abstract

The use of framework petrography is a common initial step in provenance research of sand and sandstone. The data tend to be interpreted based on the three main components quartz, feldspar, and lithic fragments. Surprisingly often, this is done without taking other influencing factors than the tectonic setting of the catchment and/or the surroundings of the depositional basin into account. Based on a database of 14 studies with approximately 900 petrographic data points from sand and sandstone, this study demonstrates quantitative effects on the apparent composition resulting from both geological and non-geological biases. The study illustrates sandstone-classification differences based on different specifications of the three end-members quartz, feldspar, and lithic or rock fragments, how the point-counting method can affect the apparent petrographic composition of sandstone, how sorting and facies bias may be differentiated from a climate or provenance signal, and how bias due to diagenetic effects can be minimised. In conclusion, both geological and non-geological biases should be considered for provenance studies that include petrographic data.

Origin of Lower Cretaceous quartzose arenites in northern India and the Indus Basins of Pakistan—The result of provenance composition, weathering or diagenesis?

“…A calculation to reconstruct the original detrital mineralogy was made from the diagenetic sequence as the changes in framework composition and texture that take place during diagenesis can obscure the provenance signal (Augustsson, 2021; Harris, 1989; Helmold, 1985; McBride, 1985). Feldspar dissolution, during eogenesis or telogenesis, results in the precipitation of feldspar overgrowths, the development of intragranular secondary porosity and precipitation of authigenic kaolinite.…”

“…Carbonate grains are classified as sedimentary rock fragments. Operator bias was addressed by following the guidelines of Augustsson (2021) and by careful identification of grain types.…”

“…Feldspar dissolution, during eogenesis or telogenesis, results in the precipitation of feldspar overgrowths, the development of intragranular secondary porosity and precipitation of authigenic kaolinite. For the reconstructions undertaken here, based on our petrographic interpretation of diagenetic processes and following the diagenetic reactions summarized in Worden and Burley (2003) and Augustsson (2021), the original feldspar total is calculated by summation of the totals for feldspar overgrowths, authigenic kaolinite and grain-replacive calcite cement. Aluminium can be mobile during diagenesis (Wilkinson & Haszeldine, 1996); therefore, this reconstruction may underestimate the original detrital feldspar content.…”

A global dataset of sandstone detrital composition by Gazzi‐Dickinson method

“…The use of framework petrography is a common step in provenance research of sand and sandstone (Augustsson, 2021; Basu, 1976; Chayes, 1956; Garzanti, 2019; Ingersoll et al, 1984; Suttner, 1976). The detrital composition of each sandstone sample was gotten by counting the grains one by one under the microscope, which would take at least 2–3 h for a skilled geologist.…”