“Coffee” in the Morning? Go see the Doctor

Mark wakes up each morning and heads to his kitchen for three cups of coffee. After showering and dressing, he goes to his job as a local disc jockey where he plays the latest “country hip hop” single releases. This genre-melding is driving Mark to madness; he often feels unbalanced, even nauseous after ripping a song or two that both twangs and beats. Think Taylor Swift, but singing about drinking and driving a pick-up after leaving her bull-rider boyfriend who skipped town and is not making child support payments. It so happens that this particular morning Mark does vomit and notices his vomitus has the appearance of coffee grounds. That morning he had complained to a technician of upper abdominal pain. Based on this scenario, where in the image is Mark likely to be experiencing pathology?

Question: Bleeding at what location can lead to coffee ground emesis?