Georeferencing Quick Reference Guide Paula F. Zermoglio, Arthur D. Chapman, John R. Wieczorek, María Celeste Luna, David A. Bloom Version 7adb86d, 2021-02-01 17:30:10 UTC Table of Contents Colophon. 1 Suggested citation. 1 Authors . 1 Contributors . 1 Licence . 1 Disclaimer . 1 Persistent URI . 1 Document control . 1 Cover image . 1 1. Introduction . 2 1.1. Objectives . 2 1.2. Target Audience . 2 1.3. Scope . 2 1.4. Changes from Previous Version . 3 1.5. Using Darwin Core . 3 1.6. Georeferencing Concepts . 5 1.6.1. Locality Type . 5 1.6.2. Corrected Center . 5 1.6.3. Radial of Feature. 6 1.6.4. Latitude . 6 1.6.5. Longitude. 7 1.6.6. Coordinate Source . 7 1.6.7. Coordinate Format . 7 1.6.8. Coordinate Precision . 8 1.6.9. Datum. 9 1.6.10. Direction . 9 1.6.11. Offset Distance . 9 1.6.12. Distance Units. 10 1.6.13. Distance Precision . 10 1.6.14. Measurement Error . 10 1.6.15. GPS Accuracy. 11 1.6.16. Uncertainty . 11 2. Georeferencing Methods by Locality Type . 11 2.1. Geographic Feature only . 11 2.1.1. Feature – with Obvious Spatial Extent. 12 2.1.2. Feature – without Obvious Spatial Extent. 13 2.1.3. Feature – Special Cases . 15 2.1.3.1. Feature – Street Address . 15 2.1.3.2. Feature – Property . 17 2.1.3.3. Feature – Path . 18 2.1.3.4. Feature – Junction, Intersection, Crossing, Confluence . 20 2.1.3.5. Feature – Cave . 21 2.1.3.6. Feature – Dive Location . 22 2.1.3.7. Feature – Headwaters of a Waterway . 23 2.1.3.8. Feature – near a Feature . 24 2.1.3.9. Feature – between Two Features . 26 2.1.3.10. Feature – between Two Paths. 27 2.2. Offsets . 28 2.2.1. Offset – Distance only . 28 2.2.2. Offset – Heading only . 29 2.2.3. Offset – Distance along a Path . 30 2.2.3.1. Offset along a Narrow Path. 32 2.2.3.2. Offset along a Wide Path . 33 2.2.3.3. Offset along Multiple Possible Paths . 34 2.2.4. Offset – Distance along Orthogonal Directions. ..