[[Image:Canada geological map-WCSB.JPG|thumb|300px|right|Outline of the Western CanadianCanada Sedimentary Basin]]
The '''Western CanadianCanada Sedimentary Basin''' ('''WCSB''') underlies {{convert|1.4|e6km2|sqmi}} of [[Western Canada]] including southwestern [[Manitoba]], southern [[Saskatchewan]], [[Alberta]], northeastern [[British Columbia]] and the southwest corner of the [[Northwest Territories]]. This vast [[sedimentary basin]] consists of a massive wedge of [[sedimentary rock]] extending from the [[Rocky Mountains]] in the west to the [[Canadian Shield]] in the east. This wedge is about {{convert|6|km}} thick under the Rocky Mountains, but thins to zero at its eastern margins. The WCSB contains one of the world's largest reserves of [[petroleum]] and [[natural gas]] and supplies much of the [[North America]]n market, producing more than {{convert|16|e9cuft|e6m3|abbr=off|order=flip}} per day of gas in 2000. It also has huge reserves of [[coal]]. Of the provinces and territories within the WCSB, Alberta has most of the [[oil]] and [[Natural gas|gas]] reserves and almost all of the [[oil sands]].