Technical note: TRACK<i>Flow</i>, a new versatile microscope system for fission track analysis

Abstract

<p><strong>Abstract.</strong> We here present TRACK<i>Flow</i>, a new system with dedicated modules for the fission track (FT) laboratory. It is based on the motorised Nikon Eclipse Ni-E upright microscope with the Nikon DS-Ri2 full frame camera and is embedded within the Nikon NIS-Elements Advanced Research software package. TRACK<i>Flow</i> decouples image acquisition from analysis to decrease schedule stress of the microscope. The system further has the aim of being versatile, adaptable to multiple preparation protocols and analysis approaches. It is both suited for small-scale laboratories and is also ready for upscaling to high-throughput imaging. The versatility of the system, based on the operators’ full access to the NIS-Elements package, exceeds that of other systems for FT and further expands to stepping away from the dedicated FT microscope towards a general microscope for Earth Sciences, <i>including</i> dedicated modules for FT research. </p> <p> TRACK<i>Flow</i> consists of a number of user-friendly protocols which are based on the well plate design that allows sequential scanning of multiple samples without the need of replacing the slide on the stage. All protocols include a sub-protocol to scan a map of the mount for easy navigation through the samples on the stage. Two protocols are designed for the External Detector Method (EDM) and the LA–ICP–MS apatite fission track (LAFT) approach, with tools for repositioning and calibration to the external detector. Two other tools are designed for large crystals, such as the Durango age standard and U-doped glass external detectors. These protocols generate a regular grid of points and inspect if each point is suitable for analysis. Both protocols also include an option to image each withheld point. One more protocol is included for the measurement of etch pit diameters and one last protocol prepares a list of coordinates for correlative microscopy. In a following phase of development TRACK<i>Flow</i> can be expanded towards fully autonomous calibration, grain detection and imaging.</p>

Exhumation of the passive margin of the DR Congo during pre- and post- Gondwana breakup: Evidence from low-temperature thermochronology, geology and geomorphology

“…MTL values for Brazilian samples are also longer, scattered between 12.5 μm and 14 μm. Track length distributions are all similar for south-eastern Brazil, showing unimodal distributions with slightly negative skewness (Van Ranst et al, 2020a). Therefore, there is a consensus that this area of the AWCO suffered intense erosion due to post-rift uplift pulses constrained to the Late Cretaceous to Palaeogene (Fonseca et al, 2021).…”

“…For this AFT study we applied the external detector method (Hurford and Green, 1983;Fleischer et al, 1975) based on the standard procedures used at the fission track laboratory at Ghent University. The AFT analyses were performed in Nikon NIS-Elements Basic Research on images acquired with the TRACKFlow system (Van Ranst et al, 2020a). We aimed at obtaining a minimum of 1000 counted spontaneous tracks (s.e.…”

“…Samples were also examined for angle-related anisotropy to assess if c-axis length projection (Ketcham et al, 2007a) is justified. D par , the etch pit diameter parallel to the crystallographic c-axis of the surface tracks, was measured using the TRACKFlow image analysis module of Van Ranst et al (2020a).…”

Tectonic History of the South Tannuol Fault Zone (Tuva Region of the Northern Central Asian Orogenic Belt, Russia): Constraints from Multi-Method Geochronology

“…Track densities were measured on a fully motorized Nikon Eclipse Ni-E microscope, equipped with a Nikon DS-Ri2 camera. The microscope and camera are linked to a computer with Nikon NIS Elements Advanced Research software, complemented with an in-house macro-enabled Microsoft Excel sheet (TRACKflow β) [32,33]. The AFT ages obtained were calculated using a total weighted mean zeta (OWMZ) of 281.6 ± 5.1 a•cm −2 , which was obtained using Durango [34] and Fish Canyon Tuff [35] age standards and IRMM 540 glass dosimeters [36].…”