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Abstract The StraboSpot data system provides field-based geologists the ability to digitally collect, archive, query, and share data. Recent efforts have expanded this data system with the vocabulary, standards, and workflow utilized by the sedimentary geology community. A standardized vocabulary that honors typical workflows for collecting sedimentologic and stratigraphic field and laboratory data was developed through a series of focused workshops and vetted/refined through subsequent workshops and field trips. This new vocabulary was designed to fit within the underlying structure of StraboSpot and resulted in the expansion of the existing data structure. Although the map-based approach of StraboSpot did not fully conform to the workflow for sedimentary geologists, new functions were developed for the sedimentary community to facilitate descriptions, interpretations, and the plotting of measured sections to document stratigraphic position and relationships between data types. Consequently, a new modality was added to StraboSpot—Strat Mode—which now accommodates sedimentary workflows that enable users to document stratigraphic positions and relationships and automates construction of measured stratigraphic sections. Strat Mode facilitates data collection and co-location of multiple data types (e.g., descriptive observations, images, samples, and measurements) in geographic and stratigraphic coordinates across multiple scales, thus preserving spatial and stratigraphic relationships in the data structure. Incorporating these digital technologies will lead to better research communication in sedimentology through a common vocabulary, shared standards, and open data archiving and sharing. 

Abstract The Paleoarchean Mt Edgar dome in the East Pilbara Terrane has long been studied as an archetypal dome within Archean dome‐and‐keel terranes, but the history of its formation is debated. Kinematic data presented in this study provide new insights into the late‐stage development of the Mt Edgar dome and East Pilbara Terrane. Quartz crystallographic preferred orientation (CPO), optical microstructures, and field structures all indicate that the granite‐greenstone contact of the Mt Edgar dome experienced reverse (greenstone‐up, dome‐down) sense of shear after the formation of the dominant schistosity. This reverse sense of shear is observed at localities along the entire extent of the sheared margin that rings most of the Mt Edgar dome, but is best documented along the southwest margin in the Warrawoona Greenstone Belt. Additionally, quartz CPO data from a dome triple junction outside of the sheared margin dominantly indicate a constrictional strain geometry, consistent with the previous interpretation that this area represents a zone of vertical foundering in a buoyancy‐instability driven system. However, buoyancy‐instability models do not necessarily predict the occurrence of greenstone‐up sense of shear preserved in solid‐state fabrics along the dome margin. Several geologic explanations are considered, including dome expansion or post‐doming deformation. The data are most consistent with explanations that directly relate to dome formation, especially when considered in tandem with recently published structural data from within the Mt Edgar dome. These kinematic data suggest that late dome development occurred in a near‐static crustal environment rather than an extensional or contractional setting. 

We present an orientation system for thin sections used for microanalysis, applicable to both billets and cores. The orientation system enables spatially referenced observations and consists of three parts. First, we establish a reference corner that is the uppermost corner of the sample on the thin section, in its original geographic orientation in the field or laboratory setting. This corner is tied to a right-hand coordinate system, in which all reference axes point downward. A geographic direction-based, rather than uppermost corner-based, convention for a reference corner can be substituted for projects that utilize sub-horizontally oriented thin sections. The reference corner - combined with orientation metadata - define a unique position of the thin section in geographic space. Second, we propose a system of small saw cuts (notches) that minimizes the number of notches required on the sample, to distinguish both the reference corner and the orientation of the thin section relative to fabric (e.g., foliation/lineation), if present. The utility of a notching standard is that it provides an inherent doublecheck on thin section orientation and facilitates sharing between users. Third, we develop a grid system in order to locate features of interest on the thin section, relative to the reference corner. Any of these systems – referencing, notching, and gridding – can be used independently. These systems are specifically designed to work with digital data systems, which are currently being developed, allowing researchers to share microstructural data with each other and facilitating new types of big data science in the field of structural geology.