Question: what is the largest magnitude earthquake that has occurred in the pacific northwest
[{'answer': 'The 1700 Cascadia earthquake', 'provenance': [{'wikipedia_id': '632101', 'title': '1700 Cascadia earthquake', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 28, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '632101', 'title': '1700 Cascadia earthquake', 'start_paragraph_id': 0, 'start_character': 0, 'end_paragraph_id': 0, 'end_character': 0, 'bleu_score': 1.0, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 10458459642497905661}, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '632101', 'title': '1700 Cascadia earthquake', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 357, 'bleu_score': 0.729734206389391, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 10458459642497905661}, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '17743962', 'title': '1949 Queen Charlotte Islands earthquake', 'section': 'Section::::Earthquake.\n', 'start_paragraph_id': 6, 'end_paragraph_id': 6, 'meta': {'evidence_span': ['the 1700 Cascadia earthquake', 'However, the greatest earthquake in Canadian history was the 1700 Cascadia earthquake, a megathrust earthquake that occurred along the Pacific Northwest coast from Northern California to southwestern British Columbia which reached magnitude 9 on the Richter magnitude scale.', 'However, the greatest earthquake in Canadian history was the 1700 Cascadia earthquake, a megathrust earthquake that occurred along the Pacific Northwest coast from Northern California to southwestern British Columbia which reached magnitude 9 on the Richter magnitude scale. Although nobody was killed in this earthquake, people and animals were knocked off their feet and there']}}]}, {'provenance': [{'wikipedia_id': '632101', 'title': '1700 Cascadia earthquake', 'section': 'Section::::Abstract.', 'start_paragraph_id': 1, 'end_paragraph_id': 1, 'meta': {'evidence_span': ['The 1700 Cascadia earthquake', 'The 1700 Cascadia earthquake occurred along the Cascadia subduction zone on January 26 with an estimated moment magnitude of 8.79.2.', 'The 1700 Cascadia earthquake occurred along the Cascadia subduction zone on January 26 with an estimated moment magnitude of 8.79.2. The megathrust earthquake involved the Juan de Fuca Plate from mid-Vancouver Island, south along the Pacific Northwest coast as far as northern California.']}}]}]