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New stratigraphic evidence from the Cascadia margin demonstrates that 13 earthquakes ruptured the margin from
 Vancouver Island to at least the California border following the catastrophic eruption of Mount Mazama. These 13 events
 have occurred with an average repeat time of ?? 600 years since the first post-Mazama event ?? 7500 years ago. The youngest
 event ?? 300 years ago probably coincides with widespread evidence of coastal subsidence and tsunami inundation in buried
 marshes along the Cascadia coast. We can extend the Holocene record to at least 9850 years, during which 18 events correlate
 along the same region. The pattern of repeat times is consistent with the pattern observed at most (but not all) localities
 onshore, strengthening the contention that both were produced by plate-wide earthquakes. We also observe that the
 sequence of Holocene events in Cascadia may contain a repeating pattern, a tantalizing look at what may be the long-term
 behavior of a major fault system. Over the last ?? 7500 years, the pattern appears to have repeated at least three times, with
 the most recent A.D. 1700 event being the third of three events following a long interval of 845 years between events T4
 and T5. This long interval is one that is also recognized in many of the coastal records, and may serve as an anchor point
 between the offshore and onshore records. Similar stratigraphic records are found in two piston cores and one box core
 from Noyo Channel, adjacent to the Northern San Andreas Fault, which show a cyclic record of turbidite beds, with thirty-
 one turbidite beds above a Holocene/.Pleistocene faunal «datum». Thus far, we have determined ages for 20 events
 including the uppermost 5 events from these cores. The uppermost event returns a «modern» age, which we interpret is
 likely the 1906 San Andreas earthquake. The penultimate event returns an intercept age of A.D. 1664 (2 ?? range 1505-
 1822). The third event and fourth event are lumped together, as there is no hemipelagic sediment between them. The age
 of this event is A.D. 1524 (1445-1664), though we are not certain whether this event represents one event or two. The fifth
 event age is A.D. 1204 (1057-1319), and the sixth event age is A.D. 1049 (981-1188). These results are in relatively good
 agreement with the onshore work to date, which indicates an age for the penultimate event in the mid-1600 s, the most likely
 age for the third event of ?? 1500-1600, and a fourth event ?? 1300. We presently do not have the spatial sampling needed
 to test for synchroneity of events along the Northern San Andreas, and thus cannot determine with confidence that the
 observed turbidite record is earthquake generated. However, the good agreement in number of events between the onshore
 and offshore records suggests that, as in Cascadia, turbidite triggers other than earthquakes appear not to have added significantly
 to the turbidite record along the northernmost San Andreas margin during the last ?? 2000 years.