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1 GSA Data Repository item A 25,000-year record of earthquakes on the Owens Valley fault near Lone Pine, California: Implications for recurrence intervals, slip rates, and segmentation models, by Steven N. Bacon and Silvio K. Pezzopane; GSA Bulletin; July/August 2007; v. 119; no. 7/8; doi: /B Figures DR1 DR11 and Tables DR1 and DR2 Figure Captions Figure DR1. Topographic map of the Alabama Hills paleoseismic site showing location of trenches (T1-T3) and exploratory pit (P1) excavated across and adjacent to the A.D Owens Valley fault rupture. Transects (A-A' through D-D') show the location of geomorphic profiles shown in Figures 4, DR2, DR3, and DR4. Figure DR2. Geomorphic profile along transect A-A' showing a non-anthropogenic modified composite scarp in relation to U.S. Highway 395 and the projection of the Owens Valley fault at depth. Reconstructed scarp profiles along transects B-B' through D-D' are based on this profile. Two wave-cut notches are evident on the profile at elevations and m. Figure DR3. Geomorphic profile along transect C-C' showing T2 in relation to U.S. Highway 395 and the projection of the Owens Valley fault at depth. Reconstructed scarp profile provides an estimate of how much the scarp was benched into during initial highway construction. Reconstructed scarp profile is based on the unmodified portion of the scarp along transect A-A' shown in Figure DR1. Two wave-cut notches are evident on the profile at elevations and 1135 m and a fluvial riser at an elevation of ~ m. Figure DR4. Geomorphic profile along transect D-D' showing T3 in relation to U.S. Highway 395 and the projection of the Owens Valley fault at depth. Reconstructed scarp profile provides an estimate of how much the scarp was benched into during initial highway construction. Reconstructed scarp profile is based on the unmodified portion of the scarp along transect A-A' shown in Figure DR1. Figure DR5. Log for the south wall of the Alabama Gates paleoseismic site P1. Lithofacies 5 and 12 are within delta plain FA-B. Lithofacies numbers and facies associations are described in Table 1 and mentioned in text. Figure DR6. Geomorphic map of the Quaker paleoseismic site showing the location of trenches (T4-T7) and pits (P2 through P3) excavated across and adjacent to the A.D Owens Valley fault rupture. Transects of Profiles 1-5 are oriented across a composite scarp that has been eroded and/or modified by shoreline and fluvial erosional processes. Figure DR7. Geomorphic scarp profiles 1 and 4-7 at the Quaker paleoseismic site (3.5x vertical exaggeration). Profiles were surveyed perpendicular to the local trend of the A.D fault.

2 Transects for each profile are shown in Figure DR6. Shoreline and fluvial erosional and constructional features have occurred at the site and have generated a composite scarp. The A.D fault rupture runs along a prominent riser at the site. Figure DR8. Trench log for the south wall of the Quaker paleoseismic site T6. A minimum of 1.0 m of apparent normal displacement related to the A.D earthquake is measured across all western faults since the deposition of lithofacies. Lithofacies numbers and facies associations are mentioned in text and described in Table 1. Figure 8 is a stratigraphic column. Figure DR9. Trench log for the south wall of the Quaker paleoseismic site T7. A minimum of 0.9 m of apparent normal displacement related to the A.D earthquake is measured across all western faults since the deposition of lithofacies 3d. Lithofacies numbers and facies associations are mentioned in text and described in Table 1. Figure 8 is a stratigraphic column. Figure DR10. Trench log for the north wall of the Quaker paleoseismic site P2. Lithofacies numbers and facies associations are mentioned in text and described in Table 1. Figure 8 is stratigraphic column. Lower contact of lithofacies 7e defines sequence boundary SB5. Figure DR11. Trench log for the east wall of the Quaker paleoseismic site P3. Lithofacies numbers and facies associations are mentioned in text and described in Table 1. Figure 8 is stratigraphic column. Lower contacts of lithofacies 4b and 14a defines sequence boundaries SB1 and SB2, respectively. DATA REPOSITORY REFERENCES Bacon, S.N., 2003, Latest Quaternary fluvio-deltaic and lacustrine stratigraphy in Owens Valley and paleoseismology on the Owens Valley fault near Lone Pine, eastern California [M.S. thesis]: Arcata, CA, Humboldt State University, 227 p. CalTrans [State of California, Department of Transportation], 1993, Project plans for construction on state highway 395 in Inyo County in and near Lone Pine from Begole Street to 0.1 mile south of Los Angeles Aqueduct bridge, 216 sheets. Reheis, M.C., Stine, S., and Sarna-Wojcicki, A.M, 2002, Drainage reversals in Mono Basin during the late Pliocene and Pleistocene: Geological Society of America Bulletin: v. 114, no. 8, p

3 1125 N 15 m Contour interval: 0.6 m A U.S. HIG HWA Y 395 A ' B B ' C T 1 T 2 P 1 C ' D' T 3 D B ase map: C alt rans (S tate of C alifornia, Department of T ransportation), 1993 Exploritory trench or pit EXPLANATION Transect of geomorphic profile Figure DR1

4 Disturbed S urface N8W 76E? Fill N25W 58E A' (east) A (west) 1125 U.S. HWY Figure DR C' (east) U.S. HWY 395 P1 T2 and reconstructed scarp profile Excavation C (west) Figure DR3 D' (east) D (west) 1125 U.S. HWY 395 T3 and reconstructed scarp profile Figure DR4

5 LITHOSTRATIGARPHIC FACIES, DESCRIPTIONS, AND FACIES ASSOCIATIONS OF STRATIGRAPHY LOCATED AT PALEOSEISMIC SITES NEAR LONE PINE, EASTERN CALIFORNIA Lithostratigraphic facies Description Facies association Depositional environment 1a,b Clayey silt, massive, firm, plastic, g reen with minor interbeded silty sand. (FA-C) offshore (deep water) 2a,b Alternating sand (fine to coarse), clayey silt, silty sand, moderately-sorted to well-sorted coarse sand, slightly hard to hard, convolute bedding, wavy and planar laminated; oxidation along bedding. Delta front (FA-A) distributary mouth bar 3a-e Sandy silt, massive, hard; contains localized vertical oxidation root casts. Delta front (FA-A; 3a) (FA-C; 3b-d) distal mouth bar nearshore 4a,b Alternating, thinly bedded (3-10 cm), light brown, silt; o r g a n i c r i c h s i l t a n d c h a r c o a l i z e d p l a n t d e t r i t u s ; diatamecous silt; massive ( cm), black peaty to organic rich silt and clay with woody debris. Delta plain (FA-B) marsh and mud flat 5a-c Alternating sand (fine to coarse), pebble (fine to coarse), g r a v e l, ( f i n e ), p o o r l y - s o r t e d t o m o d e r a t e l y - s o r t e d, subangular to well-rounded, loose to slightly hard; contains cross-bedding and localized forset bedding. Delta front (FA-A; 5a) Delta plain (FA-B; 5b,c) distributary mouth bar distributary channel 6a,b Alternating sand (fine to coarse), pebble (fine to coarse), g r a v e l, ( f i n e ), p o o r l y - s o r t e d t o m o d e r a t e l y - s o r t e d, subangular to well-rounded, loose to slightly hard; contains cross-bedding and localized forset bedding, and Alabama Hills derived lithology sand and gravel. Delta front (FA-A; 6a) Delta plain (FA-B; 6b) distributary mouth bar distributary channel 7a-e A l t e r n a t i n g s a n d ( f i n e t o c o a r s e ) a n d s i l t y s a n d, moderately-sorted to well-sorted, loose to slightly hard; contains cross-bedding, climbing ripple and planar l a m i n a t i o n, a n d l o c a l i z e d p e b b l e a n d f i n e g r a v e l ; lithofacies 7e locally cemented by tufa. Delta front (FA-A;7a) (FA-C; 7b-e) distributary mouth bar shore 8 A l t e r n a t i n g s a n d ( f i n e t o c o a r s e ) a n d s i l t y s a n d, moderately-sorted to well-sorted, loose to slightly hard; contains cross-bedding, and climbing ripple and planar lamination; localized pebble and fine gravel. Alabama Hills derived lithology sediment. Delta front (FA-A) (FA-C) distributary mouth bar shore 9a-c Pebbly, silty, sand, massive, poorly-sorted, slightly hard to hard; contains Alabama Hills lithology sand and pebble. Alluvium (FA-B) alluvial fan colluvial apron 10a-c Sand (fine to medium), well-sorted, well-rounded, loose; contains forset-bedding. Eolian (FA-B) sand dune 11 Silty sand to sandy silt, massive, slightly hard to hard; contains 10-15% angular pebbles (fine to medium) derived from the Alabama Hills. (FA-C) nearshore 12 Alternating sand (fine) and silt, moderately- to well-sorted, moderately rounded, loose to soft. Delta plain (FA-B) meandering stream 13a,b Sand (fine to medium), massive, well-sorted, well-rounded, slightly hard; locally contains platy sheets of tufa along upper boundary; lithofacies initially deposited as eolian d u n e s a n d s u b s e q u e n t l y s u b m e r g e d b y l a c u s t r i n e environment; lithofacies 13b is locally reworked. (FA-C) shore to nearshore 14a-c Sand (fine to medium), massive, well-sorted, well-rounded, slightly hard; contains subrounded to angular pebble and fine gravel size tufa fragments. (FA-C) shore (regressive facies) 15 Alternating sand (fine to coarse), moderately-sorted to well-sorted, loose to slightly hard; contains cross-bedding, and climbing ripple and planar lamination; localized pebble and fine gravel that grades into massive, hard, sandy silt; contains subrounded to angular pebble and fine gravel size tufa fragments. (FA-C) shore to nearshore 16 Silt (fine to coarse), massive, well-sorted, soft to slightly hard. Eolian (FA-B) loess c Figure DR5 PIT 1

6 N 100 m P3 P4 U.S. HIghway 395 P2 Profile 2 Owens River Profile 1 T4 T5 T6 T7 Profile 3 Profile 4 Profile 5 Owens Valley fault zone Beach ridge crest Lithologic contact Explanation Geomorphic scarp (riser) produced from lacustrine and fluvial erosional processes Fault trench or pit Transect of profile Bench mark surveyed for this study with GPS. NAD 27 CONSUS: Lat. 36 o 38' "N, Long. 118 o 04' "W, Elev..9 m Figure DR6

7 Profile 1 West 1124 Tread Beach ridge A.D fault scarp East 160 Profile 4 West 1124 Tread and riser Riser and A.D fault scarp East West Tread Profile Riser Bend in section East Riser and A.D fault scarp Figure DR7

8 East A.D fault strands 3d Channel West A.D fault strands 16 14a e 3e 13a 4b Figure DR8 TRENCH East A.D fault strands 9c 3e A.D fault strands 11 West 10c 16 14b e 15 4b TRENCH 7 Figure DR9

9 7e 1117 SB b Figure DR10 PIT b b 14a 13a 4b SB1 PIT SB2 Figure DR11

10 TABLE DR1. ELEVATION OF SHORELINE AND FLUVIAL FEATURES AND FAULT SCARPS FROM PROFILES AT THE ALABAMA GATES AND QUAKER PALEOSEISMIC SITES NEAR LONE PINE, OWENS VALLEY Paleoseismic site Profile Elevation (meters) Geomorphic feature Alabama Gates A-A' 1133 Tread surface (lacustrine) Alabama Gates A-A' Wave-cut notch Alabama Gates A-A' Meander riser Alabama Gates B-B' 1136 Wave-cut notch Alabama Gates B-B' 1132 Tread surface (lacustrine) Alabama Gates B-B' Meander riser Alabama Gates C-C' 1135 Wave-cut notch Alabama Gates C-C' 1133 Tread surface (lacustrine) Alabama Gates C-C' 1121 Meander riser Alabama Gates D-D' Tread surface (lacustrine) Alabama Gates D-D' 1121 Meander riser Alabama Gates D-D' 1117 Meander riser Quaker Profile Tread surface (fluvial) Quaker Profile Tread surface (fluvial) Quaker Profile 1 Berm crest Quaker Profile 1 Base of A.D fault scarp Quaker Profile 1 Meander riser Quaker Profile Tread surface (fluvial) Quaker Profile Riser and A.D fault scarp Quaker Profile 2.5 Wave-cut notch Quaker Profile 2 Berm crest Quaker Profile Meander riser Quaker Profile Tread and Meander riser Quaker Profile 3.5 Base of A.D fault scarp Quaker Profile 3.5 Berm crest Quaker Profile 3 Wave-cut notch Quaker Profile 3 Meander riser Quaker Profile 4 Tread surface (fluvial) Quaker Profile Tread and Meander riser Quaker Profile 4 Wave-cut notch or Meander riser Quaker Profile 4.5 Meander riser Quaker Profile 5 > Tread surface (lacustrine) Quaker Profile Meander riser Quaker Profile 5 A.D fault scarp Quaker Profile 5 Meander riser Quaker Profile Meander riser Note: Transects of profiles from the Alabama Gates paleoseismic site are shown in Figure DR1. Profile B-B' is inset Figure 3 and profiles A-A', C-C', and D-D' are shown in Figures DR2-DR4. Transects of profiles at the Quaker paleoseismic site are shown in Figure DR6. Profiles 3 and 4 are inset Figures 6 and profiles 1 and 4-5 are located in Figures DR7-10, respectively.

11 TABLE DR2. MAJOR-OXIDE COMPOSITION AND CORRELATION OF SELECTED TEPHRA LAYERS FROM OWENS VALLEY NEAR LONE PINE, EASTERN CALIFORNIA Sample SiO 2 Al 2 O 3 FeO MgO MnO CaO TiO 2 Na 2 O K 2 O Total Alabama Gates paleoseismic site, T3 OL-CST-1; (All glass) T470-7 mean (n=19) Std. Dev Reworked tephra layer from the Alabama Gates paleoseismic site. Exposed in trench (T3) and in road-cut adjacent to and north of T3 (Fig. 7). Tephra lies within diatomaceous-rich marsh or spring deposit of lithofacies 4b. Tephra is underlain by an organic rich silt that has a C age of ~12,230-10,410 cal yr B.P. (Fig. 7), therefore deposit that contains reworked tephra is less than ~10,000 cal yr B.P. Lithofacies 4b in T2 that is correlatable to T3 has a 14 C age between 10,370 and 9920 cal yr B.P. Alabama Gates paleoseismic site, T3 OL-CST-1; (Hi)FeCa T470-7 mean (n=8) Std. Dev Tephra layer using the High FeO and Ca best matches with the Wilson Creek ash beds erupted from the Mono Craters in Mono Basin. Specifically, it matches best with Wilson Creek ash beds, numbers 8-15 ( C ka; cal. ka). However, this mode of sample OL-CST-1, (Hi)FeCa is compositionally similar to all the Wilson Creek ash beds, numbers 1-19 ( C ka; cal ka). Alabama Gates paleoseismic site, T3 OL-CST-1; (Lo)FeCa T470-7 mean (n=8) Std. Dev Tephra layer using the Low FeO and Ca best matches with the Bishop ash beds, ~0.76 Ma and to the younger suite of Mono-Glass Mountain ash beds, ~0.76 to 1.8 Ma. Note: Original analytical data from electron-microprobe analysis of volcanic glass shards separated from tephra layers recovered from this study. Shards Use of trade names by the U.S. Geological Survey does not represent endoresment of the product. Calibrated ages of the tephra samples after Bard et al. (1998).

Last glacial maximum and Holocene lake levels of Owens Lake,

Quaternary Science Reviews 25 (2006) 1264 1282 Last glacial maximum and Holocene lake levels of Owens, eastern California, USA Steven N. Bacon a,, Raymond M. Burke a, Silvio K. Pezzopane a, Angela S. Jayko