Spacial sequence or order in simple words is the process of organizing of information or objects on basis of location or geography ie right to left, east to west etc. A good example is the earths layers; when talking or drawing them, you start with the top then head to the center of the earth: crust, mantle, outer core then inner core.
It depends on what the italicized phrase is. If <em>on the frozen lake </em>is italicized, then this is a prepositional phrase. Because it begins with a preposition <em>on. </em>
