Marsh Orchid?

Marsh Orchid?

Observation - Marsh Orchid?. Description: I was walking round a brownfield site today and found quite a hefty amount of orchids which must have seeded themselves in the ten years or so the site has been abandoned. One patch was very large, and contained over 100 spikes. Some were clearly Common S

I was walking round a brownfield site today and found quite a hefty amount of orchids which must have seeded themselves in the ten years or so the site has been abandoned. One patch was very large, and contained over 100 spikes. Some were clearly Common Spotted Orchid, whereas others, such as the individual pictured, looks very much like some sort of Marsh Orchid. I'm no great shakes at orchid identification, so I wondered if someone could possibly be more specific with the ID.