Those fenders are way too short to give adequate protection....
OP, look at full coverage fenders from Rene Herse or Berthoud (expensive), or Velo Orange (almost as good, and more affordable).
Those full coverage fenders are a good option. I would recommend those if this was the "commuting" forum. But, its not.
Still, it depends what "adequate protection" means to you. As stated above there are potential problems riding gravel in the wet with full coverage fenders. I've had problems with mud and snow build up that have brought me to a stop. And, I don't exactly expect to stay dry on a gravel road like I might commuting. Full coverage doesn't exactly meet the definition easy to install, where the trekking ones just slide off. Makes it great for putting the bike in/on a car too (taking a wheel off a full fender bike doesn't buy you much).
Food for thought. We all have different requirements and expectations.