1 pound halibut or red snapper, cut into 1/2-inch cubes  | 
                                                1/2 cup fresh lime juice  | 
                                                1 small red onion, diced  | 
                                                2 tomatoes, seeded and diced  | 
                                                2 jalapeƱos, seeded and finely chopped  | 
                                                1/2 cup loosely packed fresh oregano, chopped  | 
                                                1/2 cup small pitted black or green olives  | 
                                                1/2 cup fresh orange juice  | 
                                                1/2 cup tomato juice  | 
                                                1/4 cup extra-virgin olive oil  | 
                                                1 tablespoon fresh lime juice  | 
                                                1 teaspoon salt  | 
                                                1/2 teaspoon freshly ground pepper  | 
                                                garnishes: olives, lettuce leaves, or tortilla chips  |