Season the shrimp and scallops with salt and pepper. On a sheet of parchment paper arrange the scallops and shrimp with the lemon slices. Top with tarragon and tomatoes. Drizzle the olive oil over the top and seal the parchment closed by bringing to two larger ends together and fold the ends in half several times until it creates a tube. Pinch the paper eat each and and do the same thing.
Place on the lined baking sheet and bake for 20 minutes.
Transfer the package to a platter or large dish, there will be a lot of liquid inside and unwrap the package. If individual portions were made serve as is.