Heat oven to 400°F. Cut 4 (12-inch) rounds of cooking parchment paper. Place fish on half of each parchment round. Sprinkle fish with oil, marjoram, oregano, salt and pepper. Top with onion, bell pepper, tomato, zucchini and olives. Fold parchment paper over fish and vegetables. Starting at one end, fold paper tightly 2 or 3 times; twist each end several times to seal each packet.