Based on the data found in this document I created a KML file for Google Earth to visualize the data in an understandable way.
The unit of the values in the published sheet is ÁSv/h. The official limit for public people is 1000 ÁSv per year. The given values are per hour. So if we divide 1000 ÁSv by 365 days and then by 24 hrs of a day, we get a value of 0.114 ÁSv/h as the expected average dose throughout a whole year, to not exceed the limit of 1000 ÁSv.
All values you see displayed on the sheet mentioned above, lie within 0.5 and 105.0 ÁSv/hr, so quite a lot above our "expected value".
Download the KMZ file yourself (you need Google Earth to have installed to view the file) and have a look.
Link: Fukushima Radiation Map 2011-03-20. All readings can be found in the file.
The absolute maximum values are reached on hills and mountains which reach more than 800m in this area. Mountains "catch" the radiation first.