Earthquake of 597 AH

The "Fragments of Gold" (Shadharat al-Dhahab) records for 597 AH a severe famine and death in the land of Egypt, then a great earthquake in Sha'ban, which it is said spread over most of the world. ¹

Ibn al-Imad reports that the famine lasted to the middle of the year, and that human flesh was sold. He reports from Abu Shama that a tenth of the people died under the sand, and that Nablus was destroyed. He then says that the number of those who died that year was counted at eleven hundred thousand. ¹

These are figures the source gives as they stand, and the method of counting them is not known. An additional source is needed.