The OpenDocument Presentation format is a zip archive containing XML files. You can unzip it using the unzip command.
Archive: sample.odp
extracting: mimetype
creating: Configurations2/accelerator/
creating: Configurations2/images/Bitmaps/
creating: Configurations2/toolpanel/
creating: Configurations2/floater/
creating: Configurations2/statusbar/
creating: Configurations2/toolbar/
creating: Configurations2/progressbar/
creating: Configurations2/popupmenu/
creating: Configurations2/menubar/
inflating: settings.xml
extracting: Thumbnails/thumbnail.png
inflating: content.xml
inflating: meta.xml
inflating: META-INF/manifest.xml
inflating: styles.xml