It looks like that's the problem. Let's move out of plastics.
http://www.chair-mats.com/ has some options. Call them.
Can anyone recommend a Heavy Duty Plastic Carpet Protector For a Computer Chair? I bought one at Staples and OfficeMax but took them back due to the chair making dents in the plastic. I have the plastic over high carpeting and the office chair has roller on the bottom like most office chairs. The one from Stapes was 130 mil and they said that is their toughest one. I used to have one years ago that was VERY tough but forgot where I bought it and gave it away when I moved across the country.
Any suggestions for maybe an industrial type that is used in office buildings?