Kurgan (A Dark Tale From Innsmouth IV) by Ashley Lister

An excavation at a newly discovered kurgan, an ancient burial site, in Innsmouth uncovers some disturbing surprises. A senior archaeologist dies. A nefarious cult take advantage of the discoveries to further their own cause. And before long, a team from Innsmouth are travelling halfway around the world to find the relationship between their excavation and a long dead secret that yearns to rise from its grave.