Loud and repeated night-time booms have bewildered San Geronimo Valley residents for the past month. The explosions, heard and even felt from Woodacre to Lagunitas, have prompted discussions on Nextdoor and multiple calls to the Sheriff’s Office, but so far remain unexplained. “[It’s] definitely a mystery that people in the valley are following closely because it’s so loud and perplexing,” valley resident Becky Bond said. Some neighbors have pinpointed the noises, which usually occur between…