WIP: A Web-based program for indexing planar features in quartz grains and its usage

Autor(en)

Anna Losiak, Izabela Golebiowska, Ludovic Ferriere, Jacek Wojciechowski, Matthew S. Huber, Christian Koeberl

Abstrakt

Planar deformation features (PDFs) in quartz are the most important diagnostic features that allow the unambiguous identification of impact structures on Earth. In order to confirm that these features (that are characterized by planar character and form along specific crystallographic planes) are indeed PDFs, they need to be properly investigated and indexed. Following universal-stage measurements, the process of indexing is usually performed manually, using a Wulff stereonet and following a strict procedure, which is time consuming and error prone. In this article, we present WIP, a new Web-based program for indexing planar deformation features in quartz. The correctness of our program is shown by its application to measurements that had previously been indexed manually. The observed minor differences, especially in the absolute frequency percentage of PDFs, are negligible and not significant enough to influence the estimation of shock pressure that could be calculated from the indexed results. Usability of this program is shown using the spatial relationships between a statistically significant number of 278 quartz grains with 409 sets of PDFs analyzed within the area (~35 mm

²) of a single thin section of a meta-greywacke from the Bosumtwi impact structure. Our program is not only more accurate and faster than the manual (graphical) method but also removes the human error from the plotting process and allows control of several parameters, such as the value of estimated measurement error used in the indexing calculation or method of aggregated error handling. The program also provides information about the angles between the planes of the measured PDF sets present in a grain, which allows determination of the angles between (for example) indexed (101-3) and (101-1) sets.

Organisation(en)

Department für Lithosphärenforschung

Externe Organisation(en)

Polish Academy of Sciences (PAS), University of Warsaw, Naturhistorisches Museum Wien (NHM), Smart Informat Syst GmbH, University of the Free State

Journal

Meteoritics and Planetary Science

Band

51

Seiten

647-662

Anzahl der Seiten

16

ISSN

1086-9379

DOI

https://doi.org/10.1111/maps.12614

Publikationsdatum

04-2016

Peer-reviewed

Ja

ÖFOS 2012

105120 Petrologie

Schlagwörter

ASJC Scopus Sachgebiete

Geophysics, Space and Planetary Science

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/wip-a-webbased-program-for-indexing-planar-features-in-quartz-grains-and-its-usage(cb8c0c38-1079-474e-98f9-d2d342f9bf17).html