3. Hydrocarbon Resources - Offshore United States. Movement of subsurface salt deposits can produce complex structures, including salt domes and salt anticlines. When this happens, the salt that flows into domes must be withdrawn from somewhere else, causing the overlying beds to sink down to form an adjacent basin. Hydrocarbons sometimes migrate from these basins to become trapped in reservoirs adjacent to the margins of domes. Check and double- click the Problem 3a and 3b placemarks. Which feature does each placemark point to? a. Problem 3a: basin and Problem 3b: dome/anticline b. Problem 3b: basin and Problem 3a: dome/anticline