EasyGSH-DB: Petrographic maps — secondary components (short and long form) (1996, 2006, 2016)

Definition: A petrographic map is a map whose areas are grouped according to SEP-3-compliant linguistic descriptions. A SEP-3 compliant description is structured according to the format (main component 1,... HKn)(side component 1,... NKn), where the number of individual components is not limited. The SEP-3 format is based on the grain fraction designations according to DIN 4022 (Deutsches Institut für Normung, 1987), so that all grain fractions defined therein can be represented in the petrographic map as main or secondary components, from clay (not further subdivided) via mud, sand and gravel (each with subdivision into fine, medium, coarse) to stones and blocks (not further subdivided). A petrographic map is not designed for a specific purpose (compare “Figge maps” with a focus on sand fractions according to Figge, 1981), but is intended to reproduce the underlying sediment distribution from a sum curve as precisely as possible. By structuring the SEP-3 format, each petrographic map consists of a subset of “main components” and a subdata set “side components”. Each of these submaps can be created in different detail levels, in the EasyGSH project the forms “short” and “long” are used, which differ in the number and degree of detail of the individual components. Using suitable methods (Naumann et al., 2014), a histogram of the sediment distribution can be regenerated from the individual components of the most detailed variant of the petrographic submaps, from which a grain distribution in the form of a sum curve can be created via a continuation of the concept (Sievers et al., 2019). Data generation: The basis for sedimentological evaluations are surface sediment samples, which were interpolated in the context of the EasyGSH project by means of anisotropic interpolation methods and taking into account hydrodynamic factors and erosion and sedimentation processes from individual samples of different years to a grid valid for one year. At each of these grid nodes, the sediment distribution is therefore available as a sum curve. For Deutsche Bucht, this basic product is available for 1996, 2006 and 2016 in a 100 m grid, for the exclusive economic zone of Germany for 1996 in a 250 m grid. As a (quasi-)bijective reversal of the approach of Naumann et al. (2014) A SEP-3-compliant linguistic description can be generated from a sum curve (Sievers et al., 2019). In the long form, this corresponds to the format (HK1,... HKn)(NK1Q1,... NknQn), where HK stands for “main component”, NK for “side component”, Q for “quantifier” and “ad” for layer describing adjective (cf. Naumann et al., 2014). There is always at least one main component available, other main components and ancillary components may, but do not have to be present. Quantifiers (“less”, “much”,...) can, but do not have to be available for secondary components. In the detail level “long” for the petrographic maps, all the components generated, as well as for the secondary components, the quantifiers, are taken over and divided into the sub-cards, for the detail level “short” only the first two (and thus the most common) main and the first two (and thus the most common) secondary components without any existing quantifiers are taken over so far. Thus, each raster point has a linguistic description, which are summarised into areas in the case of equality. Product: Submaps of the secondary components, both in long and short form, for the Deutsche Bucht (1996, 2006, 2016) and the Exclusive Economic Zone (1996), in which the linguistic description of the component(s) is assigned as an attribute of a polygonal area. The products are provided in shape format. Literature: — German Institute for Standardisation, 2018. DIN EN ISO 14688-1: Geotechnical exploration and investigation -designation, description and classification of soil -Part 1: Designation and description (ISO 14688-1:2017), Beuth Verlag GmbH; Berlin. https://dx.doi.org/10.31030/2748424 — Figge, K., 1981. Sediment distribution in the German Bay (sheet: 2900, scale: 1:250.000). German Hydrographic Institute. Naumann, M., Waldeck, A., Poßin, W., Schwarz, C. & Fritz, J., 2014. Derivation of grain size distributions from text-based petrographic drilling material descriptions. Z. Dt. Ges. Geowiss., (165) 275-286. — Sievers, J., Milbradt, P., & Rubbel, M., 2018. Quasi-bijective mapping of sediment description and cumulative functions for coastal engineering applications. For further information, please refer to the information portal (http://easygsh.wb.tu-harburg.de/) and the download portal (https://mdi-de.baw.de/easygsh/). English Download: The data for download can be found under References, where the data can be downloaded directly or via the web page redirection to the EasyGSH-DB portal. For further information, please refer to the download portal (https://mdi-de.baw.de/easygsh/EasyEN_index.html).