[MIS31-05] Visual observation methods of outcropping volcanic structures: application for planetary volcanology
Keywords:outcrop observation, volcanic structure, photogrammetric method
The 2000 AD collapse caldera of Miyakejima volcano provides excellent outcrop of the internal structures of volcanic edifice. Because of the steep and high cliff of the outcrop refuses direct access to the outcropping structures, the analysis of the volcanic structures used photogrammetric methods based on the detailed telephotographs taken from the opposite side of the crater. Combining the numerous photographs, a three-dimensional model was reconstructed for the measurement of the size of the targets. Identification of the volcanic structures from photograph is, in some cases, difficult owing to the variation of the visual characteristics depending on the condition of the outcrop (lighting, wetting, dust cover, etc.). Observation of “type outcrop” in various conditions is crucial to cover the range of the variation of the visual characteristics of volcanic structures.