This supplement describes the data collection and processing techniques for each 6 individual component of our multi-disciplinary analysis of the rupture process of 7 the 12 January 2010 Haiti earthquake (hereafter termed the 2010 Leogane 8 earthquake). First we describe details of the finite fault modeling technique, and 9 results for single-plane fault models using teleseismic data. Next we discuss InSAR 10 data sources and detailed processing, before presenting details of the geological 11 field deployment and data collection. Finally we present alternate joint inversions to 12 our preferred kinematic rupture model (figure 3), comparing these models to the 13 preferred solution, and discussing the relative merits of each. We present two 14 alternate rupture models; a three-plane model (figure S5) to show the effects of 15 north vs. south dip for fault B, the Leogane fault; and a three-plane model exploring 16 the effects of initiating rupture on fault B rather than fault A, the EPGF-like structure 17 ( figures S6 7). 18 19
Teleseismic Bodywave Finite fault modeling 20We invert for the rupture process of the earthquake using broadband teleseismic P-21 and SH-body waveforms recorded at GSN stations worldwide. Data were selected 22 based upon quality (high signal-to-noise ratios) and azimuthal distribution. 23Waveforms are first converted to displacement by removing the instrument 24 response and then used to constrain the slip history based on the finite fault 25 inversion algorithm of Ji et al. 1 . To improve our resolution of rupture onset, 26
[1] The Septentrional fault zone (SFZ) is the major North American-Caribbean, strikeslip, plate boundary fault at the longitude of eastern Hispaniola. The SFZ traverses the densely populated Cibao Valley of the Dominican Republic, forming a prominent scarp in alluvium. Our studies at four sites along the central SFZ are aimed at quantifying the late Quaternary behavior of this structure to better understand the seismic hazard it represents for the northeastern Caribbean. Our investigations of excavations at sites near Rio Cenovi show that the most recent ground-rupturing earthquake along this fault in the north central Dominican Republic occurred between A.D. 1040 and A.D. 1230, and involved a minimum of $4 m of left-lateral slip and 2.3 m of normal dip slip at that site. Our studies of offset stream terraces at two locations, Rio Juan Lopez and Rio Licey, provide late Holocene slip rate estimates of 6-9 mm/yr and a maximum of 11-12 mm/yr, respectively, across the Septentrional fault. Combining these results gives a best estimate of 6-12 mm/yr for the slip rate across the SFZ. Three excavations, two near Tenares and one at the Rio Licey site, yielded evidence for the occurrence of earlier prehistoric earthquakes. Dates of strata associated with the penultimate event suggest that it occurred post-A.D. 30, giving a recurrence interval of 800-1200 years. These studies indicate that the SFZ has likely accumulated elastic strain sufficient to generate a major earthquake during the more than 800 years since it last slipped and should be considered likely to produce a destructive future earthquake.INDEX TERMS: 7221 Seismology: Paleoseismology;
Three trenches excavated across the central portion of the right-lateral strike-slip Wairau Fault in South Island, New Zealand, exposed a complex set of fault strands that have displaced a sequence of late Holocene alluvial and colluvial deposits. Abundant charcoal fragments provide age control for various stratigraphic horizons dating back to c. 5610 yr ago. Faulting relations from the Wadsworth trench show that the most recent surface rupture event occurred at least 1290 yr and at most 2740 yr ago. Drowned trees in landslide-dammed Lake Chalice, in combination with charcoal from the base of an unfaulted colluvial wedge at Wadsworth trench, suggest a narrower time bracket for this event of 1811-2301 cal. yr BP The penultimate faulting event occurred between c. 2370 and 3380 yr, and possibly near 2680 ± 60 cal. yr BP, when data from both the Wadsworth and Dillon trenches are combined. Two older events have been recognised from Dillon trench but remain poorly dated. A probable elapsed time of at least 1811 yr since the last surface rupture, and an average slip rate estimate for the Wairau Fault of 3-5 mm/yr, suggests that at least 5.4 m and up to 11.5 m of elastic shear strain has accumulated since the last rupture. This is near to or greater than the single-event displacement estimates of 5-7 m. The average recurrence interval for surface rupture of the fault determined from the trench data is 1150-1400 yr. Although the uncertainties in the timing of faulting events and variability in inter-event times remain high, the time elapsed since the last event is in the order of 1-2 times the average recurrence interval, implying that the Wairau Fault is near the end of its interseismic period.
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