Very difficult to write a critique for the Blue in a free study!
This has the combination of good composition, excellent colours and a good subject. It's a little bit exotic for most of us, so plenty of wow factor for those who like this type of shot.
I can understand why it scored well and you landed the blue.
A unique characteristic of Gunnuhver is that the groundwater here is 100% seawater, unlike other geothermal areas on the island. The colorful minerals in the ground provide vibrant hues, but danger is very real with temperatures over 300°C (570°F) so it is important to tread lightly and stick to the trails. Iceland´s largest mud pool resides at Gunnuhver; it is 20 meters (65 ft) wide of violently boiling earth.