<p>Animated geographic visualization is a common way to communicate spatial processes and narratives. However, authoring such animations often requires trade-offs among learnability, control, and production effort. To explore a structured authoring approach, we analyzed 64 source videos containing geographic animation segments and synthesized a design space for geographic animation targets, attributes, and effects. Based on this analysis, we designed GeoAnimation, a domain-specific declarative grammar and interactive prototype for authoring common point, line, and region animations. We examined the prototype through two use cases and expert interviews with two visualization researchers. The results provide preliminary evidence that GeoAnimation is feasible for the studied authoring tasks, while broader usability, expressiveness, and performance require further evaluation.</p> Graphical abstract <p></p>