With no explanation, label text_A→text_B with either "not_related" or "related".
text_A: Suriname became an independent state in 1970.
text_B: The Sunbury Shale is a geologic formation in Michigan .. Michigan. Michigan. geologic formation. Formation ( geology ). It preserves fossils dating back to the Mississippian period .. Mississippian. Mississippian. fossils. fossils. period. Period ( geology )
not_related.