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We present results from a natural deformed shear zone in the Turon de Técouère massif of the French Pyrenees that directly addresses the processes involved in strain localization, a topic that has been investigated for the last 40 years by structural geologists. Paleopiezometry indicates that differential stresses are variable both spatially across the zone, and temporally during exhumation. We have, however, also calculated strain rate, which remains constant despite changes in stress. This result appears to be at odds with recent experimental deformation on monophase (olivine) rocks, which indicate that strain localization occurs dominantly as a result of constant stress. We hypothesize that in the Turon de Técouère massif—and many natural shear zones—strain localization occurs as a result of reactions, which decrease the grain size and promote the activation of grain size sensitive deformation mechanisms. From a tectonics perspective, this study indicates that the deformation rate in a particular plate boundary is relatively uniform. Stress, however, varies to accommodate this deformation. This viewpoint is consistent with deformation at a plate boundary, but it is not the typical way in which we interpret strain localization.

StraboMicro provides tools for image management and data reporting for geologic data that is observed and analyzed at the microstructural scale (e.g., from thin sections). StraboMicro is part of StraboSpot (StraboSpot.org), a digital datasystem for geologic data from the macro- to the microscale, including field, laboratory, and experimental rock deformation.

StraboSpot (StraboSpot.org) is a digital data system for collection, management and sharing of geologic data from the macro- to the microscale. Due to the pandemic, it was not possible to organize field-based workshops and fieldtrips in Summer 2020 for demonstrating and eliciting community feedback on the StraboSpot data system. Rather, we decided to run a series of week-long virtual workshops to familiarize practioners with the StraboSpot data system. Workshops were organized by discipline (sedimentology, structural geology, and petrology), each with approximately 100 participants, including U.S.-based and foreign scientists. The daily structure of the workshop was a 2-3 hour block with presentations from several StraboSpot team members, followed by an afternoon help desk. We reassigned participant support costs (originally intended for field-based meetings) to provide a small ($200-250) stipend to U.S.-based participants if they agreed to fully input a data set into StraboSpot and make it publicly available. This approach to increasing engagement – which was not part of original dissemination plan – was extremely successful. Workshop participants who signed up for the stipend were generally very engaged in the data system, provided important feedback on the design and vocabulary, and are highly likely to use StraboSpot in the future. Further, it helped to populate the database. People who received the stipend also presented their StraboSpot projects to the larger group on the last day of the workshop, often with an impressive data set. Because of Covid restrictions on fieldwork in summer 2021, we intend to continue providing stipends for young professionals (graduate students, post-doctoral fellows) to use the StraboSpot system for their thesis or project-based fieldwork. In addition to getting detailed feedback, we hope these testers will become a cohort of motivated users that will teach and encourage others to use the StraboSpot data system.

The StraboSpot database allows users to permanently store and query geologic field data directly from a mobile application or through a web application at strabospot.org. The first version of the mobile application, StraboSpot, has many of the features needed to collect data in the field, including offline basemaps, a developed vocabulary, and a built-in compass. However, it was intended for use on small smartphones, and users found the form-style user interface inefficient and cumbersome to use. The newly developed StraboSpot2 packages the same core functionality of the original Strabospot into an intuitive, simple design that greatly increases data collection efficiency. Because the target device in an iPad (of any size), we were able to take a map-based approach that fits multiple different types of field workflows and expands the ability for the user to view and explore datasets. New core features include: 1) Color-coding of points and polygons by customizable geological unit tags or conceptual tags; 2) Viewing all data collected at a spot in a “notebook view”; 3) Making sketches or annotate photographs; 4) Filtering spots, images, or tags by map extent; and 5) Facilitating the back up of datasets using integration with the iPadOS file system. StraboSpot2 is developed in React Native, a cross-platform development environment. This development environment will allow future versions to possibly support iPhone (iOS) and Android devices.

StraboExperimental: • A web-based application (under development) for experimental data • Goal is to make experimental data FAIR • We have developed an apparatus repository where equipment data are housed and can be quickly accessed to increase the efficiency of uploading experimental data • One component of experimental data is large time-series data files: we are developing prescribed headers for fast data input • Future developments will allow users to query and plot data from various sources

StraboSpot is a geologic data system that is designed to allow researchers to digitally collect, store, and share both field and laboratory data (Walker, J.D., et al., 2019, StraboSpot data system for Structural Geology, Geosphere). It was designed originally for structural geology data, but has been extended to field-based sedimentology and petrology, experimental deformation, and microanalysis. The data system uses two main concepts - spots and tags - to organize data. A spot characterizes a specific area at any spatial scale of observation. Spots are related in a purely spatial manner, and consequently, one spot can enclose multiple other spots that themselves contain spots. Spatial data can thus be tracked from scales of 100’s of km (regional) to several nanometers (microscopic). Tags provide conceptual grouping of spots, allowing linkages between spots independent of their spatial position. We will highlight the current development of the microstructural component of StraboSpot for the desktop environment. The vocabulary underlying this system was developed with participation from EPOS. The use of spatially nested spots and conceptual grouping by tags works identically to the field-based application. Micrograph images obtained through different instruments may be stored, retaining spatial relations between images, along with associated data. The micrograph application will be interoperable with field data, as well as with experimental rock deformation data, providing geologic context for all samples. We will incorporate other communities that participate in microstructural analysis (igneous, metamorphic, and sedimentary petrology), after we complete a working version for the structural geology community.