CHART ACCURACY Owing to the age and quality of the source information, some detail may not be positioned accurately. Positions obtained from Global Navigation Satellite Systems, such as GPS, are normally referred to WGS84 Datum. The differences between satellite-derived positions and positions on this cell cannot be accurately determined. Mariners are warned that these differences MAY BE SIGNIFICANT TO NAVIGATION and are therefore advised to confirm GPS positions shown in the chart display using alternative navigational techniques particularly when closing the shore or navigating in the vicinity of dangers.