Wow, that's freaky. But solar would be oriented to the south or at least all inteh same direction. These vary from straight south to north east. In google earth the largest ones in teh northern area seem to be mounds with wedges cut out of them. I'm thinking a Thai version of a burial mound.
http://www.golfingguidesthailand.com/s-Bangphra%20Golf%20Course
http://diary.00ff00.com/wp-content/photos/chinese-cemetary.jpg