B Annulus : An outside annulus, one out from the A annulus, usually production casing x production casing or surface casing. (Note, there may be regional differences in the A, B, C annulus designations)
George E. King Engineering, 5000 Oilfield Terms: A Glossary of Petroleum Engineering Terms, Abbreviations and Acronyms, US 2010. http://gekengineering.com/Downloads/Free_Downloads /Glossary_of_Petroleum_Engineering_Terms_25_August _2010.pdf, (Oil - Amer) {593}