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To identify jurisdictions and demographic factors associated with increased driving times to the nearest RT facility in Canada. RT facilities in Canada were identified using information obtained from the Canadian Association of Radiation Oncology and the IAEA Directory of Radiotherapy Centers. The 2021 Canadian census was used to determine demographic profiles for each dissemination area, the smallest geographic unit (target size 400-700 people) on which all census data is reported. Poor geographic access was defined as a driving time between a dissemination area and the closest RT facility exceeding 90 minutes as computed using the OpenStreetMap database. The association between province and poor geographic access was assessed using multivariable logistic regression adjusting for population density by decile. Demographic characteristics were subsequently introduced into the logistic regression to identify factors associated with poor access. A total of 51 radiotherapy centers and 57,937 dissemination areas were mapped. Median driving time to the closest RT facility was 23 minutes, and 13% of the population had poor access to RT. RT was least accessible in the three territories, whose residents had a median driving time of 1096 minutes. Among the provinces, Newfoundland had the longest median driving time of 91 minutes while Manitoba had the shortest median driving time of 20 minutes. On logistic regression with population density as a covariate, dissemination areas in Newfoundland (OR, 9.64 compared to Ontario; 95% CI, 8.3 to 11.2) and British Columbia (OR, 5.46; 95% CI, 5.03 to 5.93) had the highest odds of poor geographic access, whereas Ontario (reference) and PEI (OR, 0.49; 95% CI, 0.34 to 0.69) had the lowest odds. Inclusion of demographic variables in the logistic regression revealed that dissemination areas with higher median age (OR, 1.035 per year; 95% CI, 1.030 to 1.039), more males (OR, 1.033 per %; 95% CI, 1.021 to 1.045), lower income (OR, 1.030 per % low income status; 95% CI, 1.024 to 1.035), increased aboriginal representation (OR, 1.050 per %; 95% CI, 1.045 to 1.054), fewer visible minorities (OR, 0.979 per %; 95% CI, 0.973 to 0.985), fewer immigrants (OR, 0.934 per %; 95% CI, 0.927 to 0.941), and lower attainment of postsecondary education (OR, 0.976 per %; 95% CI, 0.972 to 0.979) were associated with poorer access to RT. Approximately 13% of Canadians have a driving time exceeding 90 minutes to the closest RT facility. Geographic access to RT varied by province and dissemination areas with higher median age, low socioeconomic status, a greater proportion of males, and higher aboriginal populations were associated with poorer access. Our study identified deficiencies in access to existing RT facilities, and its results may inform planning efforts for locations of new facilities in Canada. [ABSTRACT FROM AUTHOR]

[Display omitted] • Mineral prospectivty mapping for Au. • Random forest algorithm for integrating geoscience data. • Knowledge-based algorithms. • Superior tectonic province. This paper uses the random forest (RF) algorithm to produce two maps of orogenic gold prospectivity (MPM) across the entire Superior geologic province of Ontario and Quebec, Canada. One MPM of this entire study area is based on a compilation of mapped faults while the other is based on a manual interpretation of lineaments from airborne magnetic data. In addition, we have created four MPMs over the Abitibi region as the MPM map of the entire Superior is characterized by a mapping bias due to more intense mapping of faults over the Abitibi portion of the study area with respect to the rest of the Superior province. There are three RF maps generated over the Abitibi region based on faults, fault density and fault intersection density, faults + magnetic data and faults + gravity + magnetic data. To reduce the effect of the fault mapping bias, we developed a fourth map based on a knowledge driven (weighted sum technique). Statistically the best MPM is based on the faults, gravity and magnetic data. The major predictors of gold are NW-SE, NE-SW, EW trending faults, fault intersection density between EW and NW trending faults and to a lesser extent fault density and a magnetic vertical gradient image. In addition, we compare two greenstone belts in three dimensions with respect to their potential for gold exploration. We conclude that the Larder Lake greenstone belt is more fertile with respect to gold mineralization than the Swayze greenstone belt due to deeper penetrating faults which have greater potential for tapping gold mineralized fluid from the mantle or lower crust. Our final MPM map has identified prospective areas that contain known gold mines as well as areas that do not contain any known gold mines. These prospective areas may be prime for orogenic gold exploration. [ABSTRACT FROM AUTHOR]