We present a new strategy for extracting information on the thermal history of sedimentary samples that lost part of their radiogenic helium during sediment burial. It uses combined U/Pb and (U-Th)/He dating of zircon to find grains that formed just before deposition and use them to model the basin thermal history. The model also estimates the time when the source rock of each grain cooled. We discuss the advantages and limitations of our approach and its application to other methods.