Subsurface Structure of the East Bay 

Plain Ground-Water Basin: San 

Francisco Bay to the Hayward Fault, 

Alameda County, California 

By R.D. Catchings1, J.W. Borchers1, M.R. Goldman1, G. Gandhok1, 

D.A. Ponce1

, and C.E. Steedman1

Open-File Report 2006-1084 

2006 

Any use of trade, firm, or product names is for descriptive purposes only and does not imply 

endorsement by the U.S. Government. 

U.S. DEPARTMENT OF THE INTERIOR 

U.S. GEOLOGICAL SURVEY 

1 U.S. Geological Survey, 345 Middlefield Rd, Menlo Park, CA 94025 

1
2

Introduction 

The area of California between the San Francisco Bay, San Pablo Bay, Santa 

Clara Valley, and the Diablo Ranges (East Bay Hills), commonly referred to as the “East 

Bay”, contains the East Bay Plain and Niles Cone ground-water basins (CDWR, 1967)

(Fig. 1). The area has a population of 1.46 million (2003 US Census), largely distributed 

among several cities, including Alameda, Berkeley, Fremont, Hayward, Newark, 

Oakland, San Leandro, San Lorenzo, and Union City. Major known tectonic structures in 

the East Bay area include the Hayward Fault and the Diablo Range to the east and a 

relatively deep sedimentary basin known as the San Leandro Basin (Marlow et al., 1999; 

Stanley et al., 2002; Ponce et al., 2003) beneath the eastern part of the bay. Known active 

faults, such as the Hayward, Calaveras, and San Andreas pose significant earthquake 

hazards to the region, and these and related faults also affect ground-water flow in the 

San Francisco (SF) Bay area (Izbicki et al., 2003). Because most of the valley 

comprising the San Francisco Bay area is covered by Holocene alluvium or water at the 

surface, our knowledge of the existence and locations of such faults, their potential 

hazards, and their effects on ground-water flow within the alluvial basins is incomplete. 

To better understand the subsurface stratigraphy and structures and their effects 

on ground-water and earthquake hazards, the U.S. Geological Survey (USGS), in 

cooperation with the East Bay Municipal Utility District (EBMUD), acquired a series of 

high-resolution seismic reflection and refraction profiles across the East Bay Plain near 

San Leandro in June 2002 (Fig. 2). In this report, we present results of the seismic 

imaging investigations, with emphasis on ground water. 

Geology and Tectonics 

The San Francisco Bay area is located within a relatively wide segment of the 

North American-Pacific plate boundary consisting of a number of active right-lateral, 

strike-slip fault zones, including the San Gregorio, San Andreas, Hayward-Rodgers 

Creek, Calaveras, and other smaller fault zones (Wallace, 1990; Graymer, 2000). The San 

Francisco Bay lies within a structural depression between the Diablo Range (East Bay 

Hills) to the east and the Santa Cruz Mountains to the west (Fig. 1). Within the structural 

depression, areas between the bay and the mountain ranges are largely covered by 

Quaternary alluvium (Graymer, 2000). On the eastern side of the bay, the alluvialcovered areas extend about 6 to 15 km from the bay to rock exposures in the Diablo 

Range. The alluvium and underlying sedimentary units consist largely of late Pleistocene 

to Holocene unconsolidated marine and continental deposits (Muir, 1993; Figuers, 1998). 

The marine deposits are largely estuarine mud and salt-marsh deposits, known as Young 

Bay Mud, Old Bay Mud or the Yerba Buena Mud (Sloan, 1992)), and other minor units 

(Trask and Rolston, 1951; Ross, 1977; Atwater et al, 1981; Rogers and Figuers, 1991; 

Sloan, 1992; Ch2M-Hill, Inc., 2000). The continental deposits are mostly coarse-grained 

stream-channel deposits and finer-grained flood-plain deposits (Sloan, 1992; Koltermann 

and Gorelick, 1992) that were deposited as coalescing alluvial fans of San Leandro, San 

Lorenzo, and Alameda Creeks and other drainages along the east side of the San 

Francisco Bay. Partly consolidated sedimentary rocks and deposits probably underlie the 

late Pleistocene continental and marine deposits in much of the southern East Bay Plain 

(Marlow and others, 1999; Izbicki and others, 2003). 

In the region, basement rocks beneath the valleys are assumed to be the same as 

those found in the adjacent mountain ranges, which consist largely of Mesozoic Great 
3

Valley and Franciscan complexes, and overlying Tertiary and younger rocks (Howard, 

1979; Graymer, 2000). In the study area, the Great Valley complex is principally 

composed of dismembered ophiolite and silicic volcanic rocks, which are overlain by 

Late Jurassic silicic tuff and tuffaceous sandstone, Late Jurassic to Early Cretaceous 

turbidites, and Late Cretaceous and Paleocene strata (Graymer, 2000). The Franciscan 

complex is composed of multiple rock types, including graywacke, metagraywacke, 

metachert, metabasalt, turbidites, sandstone, quartz diorite, and serpentinite (Graymer, 

2000). The Tertiary strata consist of various sedimentary and volcanic rocks, which were 

probably deposited unconformably over the Mesozoic Rocks (Graymer, 2000). Within 

the East Bay Hills, late Cenozoic faulting and folding (Aydin, 1998; Unruh and Lettis, 

1998) have deformed the sequence of rocks. 

Hydrogeology 

Historically, aquifer descriptions were extended into the East Bay Plain from the 

Niles Cone ground-water basin to the south (Brown and Caldwell, 1986; Maslonkowski, 

1988). The four aquifers defined in the Niles Cone ground-water basin from shallowest 

to deepest are the Newark, Centerville, Fremont, and Deep aquifers. Generally, in the 

East Bay Plain sedimentary deposits that correlate with the Newark aquifer in the Niles 

Cone ground-water basin lie between depths of 9-40 m (30-130 ft) below land surface 

(CH2M HILL, 2000). Near the San Francisco Bay these deposits have been intruded by 

seawater. In the East Bay Plain sedimentary deposits that are correlative with the 

Centerville and Freemont aquifers in the Niles Cone ground-water basin are 

discontinuous lenses of sand and gravel interbedded with clays and silts between about 

36 and 122 m (120-400 ft) below land surface. Most useable ground water is stored in 

the Centerville and Fremont equivalent deposits and in the Deep aquifer which lies 

between about 152 and 198 m (500-650 ft) below land surface in the study area. The 

aquifer system in the East Bay Plain consists of often discontinuous deposits of alluvial 

sand and gravel with some aeolian sand, separated by estuarine mud or fine-grained 

alluvial flood plain deposits. 

 In the East Bay Plain ground-water basin, the Deep aquifer is thickest and most 

continuous south of San Leandro (Izbicki et al., 2003). Luhdorff and Scalmannini (2003) 

proposed that a stratigraphic or structural transition partly restricts hydraulic 

interconnection within the Deep aquifer between the East Bay Plain and Niles Cone 

ground-water basins. They identified eight distinct coarse-grained stratigraphic units 

within the Deep aquifer underlying the southern East Bay Plain and within their transition 

zone. Sediments comprising the Deep aquifer in the study area may have been deposited 

further south, in the alluvial fan of Alameda Creek, and moved to the northwest by rightlateral motion on the Hayward Fault (Maslonkowski, 1988; Koltermann and Gorelick, 

1992). 

Considerable hydraulic connection between the two ground-water basins has been 

demonstrated only in the Deep Aquifer (Luhdorff and Scalmannini, 2003). Ground water 

in sediments overlying the Deep aquifer generally flows from east to west from the 

Oakland Hills to San Francisco Bay (SF Bay Regional Water Quality Board, 2004; 

CH2MHill, 2000). Ground-water flow in the Deep aquifer may have a northerly 

component that has not been seen in the shallower aquifer system. 

Knowledge of the aquifer system in the study area is principally derived from 

drillers’ reports and associated bore hole geophysical logs collected from production and 

monitoring wells. Because of the complex depositional environment, where alluvial fan 

deposits interfinger with estuarine deposits, and because wells are spread widely over the 
4

ground-water basin, it is difficult to correlate stratigraphy from well to well. Highresolution seismic imaging methods, like those presented in this report, combined with 

well-log data, provide a means to more closely correlate stratigraphic horizons and 

structural complexity that affect ground-water flow across the East Bay Plain. 

Seismic Survey 

Data Acquisition 

In June 2002, the USGS acquired a ~6-km-long, high-resolution seismic transect 

from the SF Bay to the Hayward fault (Fig. 1). Most (~4.2 km) of the transect trended 

along San Lorenzo (SL) Creek, and the remaining segments were acquired along 

accessible paths toward the Hayward Fault (Fig. 2). For ease of processing the data, we 

divided the transect into six nearly linear segments or “profiles”, here referred to as 

profiles SL-1 through SL-6. Acquisition parameters are presented in Table 1. 

We used a combination of Betsy-SeisgunTM blasts, down-hole explosive blasts, 

and dropped weights as seismic sources. Betsy SeisgunTM blasts consisted of 400-grain 

shotgun blanks in 0.3-m-deep holes, and down-hole explosive sources consisted of ~150-

g (1/3 lb.) pentolite explosives in 2-m-deep holes. Along paved streets near the Hayward 

fault, we used an accelerated weight-drop source, borrowed from Lawrence Livermore 

National Laboratory. The combination of seismic sources was spaced at 5-m increments 

along the seismic profile, except where cultural features limited their use. 

The data were recorded using an array of four Geometrics StrataviewTM RX 60 

seismographs, each with 60 active channels (240 total active channels), mated to 40-Hz, 

single-element, Mark Products L-40ATM vertical geophones. The geophones were spaced 

at 5-m increments along the profile and co-located (1-m separation) with the seismic 

sources. Shot timing was determined electronically at the seismic source when a 

hammer, used to trigger the seisgun, electrically closed contact with the Betsy SeisgunTM, 

sending an electrical signal to the seismograph. The weight-drop source similarly 

triggered the seismographs electronically upon impact with the ground surface. For the 

explosive source shots, seismographs and seismic sources were manually triggered, and 

timing was determined from up-hole times at the co-located geophones. 

Data were acquired using a shoot-through acquisition technique, whereby 

recording sensors remained stationary as shots were fired through the actively recording 

array. Typically, shots were fired through one-half to three-quarters of the active array 

before the southwestern 60 channels were moved to the northeastern end of the active 

array. This process of moving the seismic array was utilized for all segments of the 

profile that were longer than 1200 m. Three seconds of data were recorded for sources 

generated by the Betsy SeisgunTM and weight-drop, and five seconds of data were 

recorded for the explosive shots. The data were recorded in SEG-2 format on the hard 

drive of GeometricsTM seismographs during field acquisition and were later transferred to 

4-mm tape in SEG-Y format for long-term storage. 

Table 1. Acquisition parameters for Profiles SL-1 though SL-6. Distances are relative to the first and last 

geophone. Cumulative length does not include recording lapse. 

Profile # Orientation Length of 

geophone 

profile (m) 

Length of 

shot point 

profile (m) 

No. 

of 

shots 

No. of 

CDPs 

Max 

fold 

Cumulative 

Length (m) 

(geophones) 

Profile SL1 SW-NE 2833 2799 538 1153 168 2833 

Profile SL2 W-E 729 708 148 311 148 3562 

Profile SL3 W-E 673 673 130 287 130 4235 

Profile SL4 SW-NE 270 260 26 107 26 4505 
5

Profile SL5 SW-NE 284 244 39 95 39 4789 

Profile SL6 SW-NE 574 574 115 233 115 5363 

Shot-point and Receiver Locations and Theoretical Fold 

Prior to acquiring the seismic data, geophone and shot locations were surveyed 

using a measuring tape. After acquiring the data, geodetic positions of every shot 

location and every 20th geophone position were determined using either a differential 

Global Positioning System (GPS) or an Electronic Distance Measurement ((EDM) 

instrument. Surveyed locations may be accurate to within 0.05 m. Locations of 

geophones that were not surveyed were interpolated from the surveyed geophone 

locations. 

Lateral variations in the elevations of shot points and receivers may cause 

inaccuracies when stacking reflection data and when determining velocities if the 

variations are not included in processing. We have accounted for these elevation 

variations during data processing but we include profile geometries in Appendices A-G 

for reference. Graphical displays of the profile geometries are also presented, including 

plots of shot and geophone elevations, shot and geophone lateral variations, and fold 

(Figs. 3-8). 

Profile SL 1 

 Profile SL 1 was oriented southwest-northeast, and it extended 2833 m along the 

southern side of San Lorenzo Creek from the San Francisco Bay to Washington Avenue 

(Fig. 2). A total of 538 shots were fired, with 43 shot points not utilized due to cultural 

features. Geophone elevations varied by about 8 m over a distance of about 2833 m (Fig. 

3a), and the geophone array deviated laterally from a linear array by 89 m (Fig. 3b), 

which is about a 3% lateral variation relative to profile length. Shot point elevations 

varied about 7 m along the 2799-m-long shot point array (Fig. 3c) and varied laterally 

from a linear array by about 88 m (Fig. 3d). For purposes of stacking the reflection data, 

fold along SL-1 varied with distance along the profile because of changes in geophone 

placement described above. Maximum fold was greater than 160, decreasing to 1 at the 

ends of profile SL-1 (Fig. 3e). 

Profile SL 2 

 Profile SL-2 was oriented west to east, and it extended 729 m along the northern 

side of San Lorenzo Creek from Washington Avenue to Embers Way at the I-880 

freeway. Three RX-60 seismographs with 159 active channels were used to record the 

data. A total of 148 shots were fired, with five shot points not utilized due to cultural 

features. Geophone elevation varied by about 4 m along the 729-m-long profile (Fig. 4a), 

and the geophone array varied laterally by about 58 m relative to a linear array of the shot 

points, an approximately 8% lateral variation relative to profile length (Fig. 4b). Shot 

point elevations varied by about 4 m along the 708-m-long shot point array (Fig. 4c), and 

shot points varied laterally from a linear array by about 44 m (Fig. 4d), a 6% variation. 

Theoretical stacking fold along SL-2 varied smoothly along the profile because of the 

stationary recording array, with a maximum fold of 148 near the center, decreasing to one 

at the ends of the profile (Fig. 4e). 

Profile SL 3 

 Profile SL 3 was oriented west to east, and it extended 673 m along the northern 

side of San Lorenzo Creek from the I-880-freeway overpass at Hesperian Boulevard to 
6

the Southern Pacific railroad tracks at Lewelling Boulevard. Three RX-60 seismographs 

with 144 active channels were used to record the data. A total of 130 shots were fired, 

with 14 shot points were not utilized due to cultural features. Geophone elevation varied 

across the 673-m-long profile by about 2.5 m (Fig. 5a), and the geophone array varied 

from a linear array by about 47 m (Fig. 5b), an approximate 7% lateral variation relative 

to the profile length. Shot point elevations also varied by about 2.5 m along the 673-mlong shot point array (Fig. 5c), with shot points varying laterally relative to a linear array 

by about 46 m (Fig. 5d). Fold along SL-3 varied smoothly along the profile because of 

the stationary recording array. Maximum fold was 130 near the center of the profile, 

decreasing to one at the ends of the profile (Fig. 5e). 

Profile SL 4 

 Profile SL 4 was oriented southwest-northeast, originating at the Southern Pacific 

railroad tracks (north of Lewelling Blvd.) and extending northeast 270 m across the 

athletic fields of San Lorenzo High School. One RX-60 seismograph with 55 live 

channels was used to record the data. A total of 26 shots were fired, with 29 shot points 

not utilized within the confines of the school’s football field. Geophone elevation varied 

across the 270-m-long survey by about 1.6 m (Fig. 6a), and the geophone array varied 

laterally relative to a linear array by about 1 m (Fig. 6b), approximately a 0.4% lateral 

variation relative to the profile length. Shot point elevations also varied about 2 m along 

the 260-m-long shot point array (Fig. 6c), with a lateral variation relative to a linear array 

of about 1.2 m (Fig. 6d). Fold along SL-4 varied considerably across the profile because 

of the missing shot points across the football field (Fig. 6e). A maximum fold of 26 was 

obtained near the middle of the profile. However, much of the western half of the profile 

had a fold of only three due to the unused shot points. Fold decreased to one at the ends 

of the profile. 

Profile SL 5 

 Profile SL 5 was oriented southwest to northeast (Fig. 2). The profile originated 

at Ashland Avenue and the southwest entrance to Edendale Park, and it extended 284 m 

northeast to the northeastern corner of Edendale Park. One RX-60 seismograph with 58 

active channels was used to record the data. A total of 39 shots were fired, with 19 shot 

points not utilized due to cultural features such as sprinklers and a children’s playground. 

Geophone elevation varied by about 1.3 m along the 284-m-long profile (Fig. 7a), with 

the geophone array varying laterally from a linear array by about 2.1 m (Fig. 7b), an 

approximately 0.7% lateral variation relative to the profile length. Shot point elevations 

also varied about 1.3 m along the 244-m-long shot point array (Fig. 7c), with lateral 

variation relative to a linear array of about 2 m (Fig. 7d) or about 0.8%. Fold along SL-5 

varied smoothly across the profile because of the stationary recording array. Maximum 

fold was 39 near the center of the profile, decreasing to one at the ends of the profile 

(Fig. 7e). 

Profile SL 6 

 Profile SL 6 was oriented southwest to northeast (Fig. 2). The profile extended 

574 m from near the corner of E-14th Street and 163rd Avenue (on the northwestern side 

of 163rd Avenue) to Liberty Street at the I-580 freeway. Two RX-60 seismographs with 

117 active channels were used to record the data. A total of 115 weight-drop sources 

were used, with two shot points not utilized due to cultural features. Geophone elevation 

varied by about 11 m across the 574-m-long profile (Fig. 8a), with the geophone array 
7

varying laterally relative to a linear array by about 2.5 m (Fig. 8b), approximately a 0.4% 

lateral variation relative to profile length. Shot point elevations also varied by about 11 

m along the 574-m-long shot point array (Fig. 8c), and the shot point array varied relative 

to a linear array by about 4.9 m (Fig. 8d). Fold along SL-6 varied smoothly along the 

profile because of the stationary recording array. Maximum fold was 115 near the center 

of the array, decreasing to one at the ends of the profile (Fig. 8e). 

Seismic Imaging Method 

Because of the shoot-through acquisition method, we developed reflection and 

refraction images from the same data. Individual profiles were analyzed separately, but 

we present them here as a composite image so that the images can be seen in the context 

of the entire seismic profile. However, we describe specifics of data processing and 

inversion for each profile so that possible anomalies and artifacts can be pointed out. 

Data Analysis 

 First-arrival refractions from usable seismograms were used to develop a P-wave 

tomographic velocity model of the shallow subsurface along each seismic profile. We 

used a modified version of an algorithm by Hole (1992), whereby we parameterize the 

starting model into 5-m by 5-m vertical and horizontal grids. As a check on the validity 

of the model, we utilized multiple starting models, all of which yielded similar final 

models. Velocities were measured at depths ranging from about 3 m below the ground 

surface (bgs) to maximum depths of about 120 m bgs. The depth of velocity imaging 

was largely determined by the maximum distance that clear first arrivals could be 

observed on the seismic records. Because of the noisy urban environment, clear first 

arrivals were typically observed to lateral distances of about 600 m or less from the 

source. For greater depths, velocities needed for seismic reflection stacking were 

determined using semblance, parabolic methods, and apriori knowledge of the local 

geology, derived by combining borehole and empirical data. We also used the inversionderived velocities to convert the reflection time images to depth images and to migrate 

the seismic reflection images. 

 

Seismic Refraction Images 

Composite Velocity Image 

Near-surface velocities along profile SL-1 vary from 900 m/s near the 

northeastern end of the profile to about 1400 m/s at the southwestern end of the profile 

(Fig. 9). At approximately 100 m depth, velocities range from 1800 m/s on the 

southwestern end of the profile to about 2000 m/s on the northeastern end. Near-surface 

velocities along SL-1 are generally greater near the bay (southwest end of the profile) 

than those farther to the northeast. Because P-wave velocities in relatively thick 

sequences of unconsolidated and saturated sediments are typically at least 1500 m/s (Nur, 

1982; Schon, 1996), we can use the 1500 m/s velocity contour (white contour, Fig. 9) to 

infer lateral variations in the top of continuously water-saturated sediments along the 

profile. However, because the model is a smoothed average over vertical and lateral 

distances of about 10 to 15 m (2 to 3 grids), the 1500 m/s velocity contour probably infers 

relative depth variations, not the exact depths of continuously saturated sediments. 

Another factor that may influence the velocity variations is the presence of faults, which 

can result in shallower depths to the 1500 m/s velocity contour in saturated rocks 
8

(Mooney and Ginzburg, 1986). Thus, some of the vertical variation in the depth of the 

1500 m/s velocity contour may be related to faulting and fracturing. 

On the basis of variations in the depth of the 1500 m/s velocity contour across the 

East Bay Plain, we suggest that, generally, the water table is shallowest near the San 

Francisco Bay and deepens toward the Hayward Fault. However, there are several local 

variations in the depth of the 1500 m/s contour that suggest the depth to the water table 

changes or shallow-depth sediments have been disrupted by faulting. Along profile SL-1, 

two distinct zones with relatively greater depths to the 1500 m/s velocity contour are 

centered near meters 250 and 2300 of the seismic profile. These zones are also seen as 

anomalies in the seismic reflection images, and as discussed below, the zones may 

correlate with significant shallow-depth faulting. 

Velocities along profile SL-2 vary from 800 m/s at the surface to 1900 m/s at a 

depth of about 100 m (Fig. 9). Across much of the seismic profile, the depth to the 1500 

m/s velocity contour does not vary significantly. However, there is appreciable variation 

in the depth of the 1500 m/s contour near the ends of the seismic profile. We cannot rule 

out possible edge effects, resulting from too few raypaths at depth near the ends of the 

array, as causing the depth variations near the ends of the profile. However, as discussed 

below, we conclude that the apparent variation in the depth of the 1500 m/s velocity 

contour near the northeast end of the profile is probably due to lateral changes in 

structure and/or composition. Generally, near-surface velocities are lower along profile 

SL-2 relative to those along profile SL-1, particularly along the northeastern section of 

the profile. Lateral complexities in the higher-velocity (deeper) strata (> 1500 m/s) are 

probably related to lateral variations in composition or structure along the profile. 

Near-surface velocities along profile SL-3 vary from 800 m/s on the southwest 

end of the profile to 1100 m/s on the northeast end. At depths of about 80 m, maximum 

velocities are about 1850 m/s along the profile (Fig. 9). The 1500 m/s velocity contour, 

which is outlined in white on the velocity image, varies from about 20 m to about 35 m 

deep along the seismic profile, with the greatest depth occurring near the northeast end of 

the profile. The greater depths to the 1500 m/s contour near the northeast end of the 

profile may be related to raypath edge effects, but we suggest that the greater depths are 

related to structural or compositional variations based on two observations. First, the 

1500 m/s velocity contour deepens more than 100 m southwest from the northeast end of 

profile SL-3. Ray-path edge effects are unlikely to occur that far from the end of the 

profile, especially at shallow depths. Second, the 1500 m/s contour is deep at both the 

northeastern end of profile SL-3 and the southwestern end of profile SL-4. Higher 

velocities (>1700 m/s) also show appreciable lateral variation, suggesting considerable 

structural or compositional variation at depth. 

Due to the relatively short length of profile SL-4, we obtained velocities to 

maximum depths of only 40 m. Near-surface velocities along profile SL-4 vary from 800 

m/s to 1100 m/s (Fig. 9), with the highest near-surface velocities near meter 100 of the 

seismic profile. The relatively higher near-surface velocities are likely due to soils with 

high water content on the San Lorenzo High School football field, which recently had 

been seeded and was being watered during data acquisition. From the near surface to 

about 40 m below land surface, velocities increase to about 2000 m/s, which are high 

relative to those along profiles SL-1 through SL-3. For velocities greater than about 1200 

m/s, the velocity contours largely dip to the southwest, suggesting more structural or 

compositional complexity toward the southwest. In particular, the 1500 m/s velocity 

contour dips southwestward, and it largely coincides with the 1500 m/s velocity contour 

near the northeastern end of profile SL-3. These similar variations in velocity near the 
9

adjoining ends of the two profiles suggest structural or compositional anomalies in this 

vicinity of the East Bay Plain.

The relatively short length of profile SL-5 (~300 m) limited our velocity 

measurements to maximum depths less than 50 m along the profile. Near-surface 

velocities range from 700 to 900 m/s, with minor lateral variation in velocity or depth of 

velocity contours (Fig. 9). The velocity gradient in the upper 20 m is high, reaching 1500 

m/s at about 18 m and about 2000 m/s at depths less than 40 m. Low-velocity sediments 

(< 1500 m/s) do not vary appreciably in depth along the profile, but higher-velocity (> 

1500 m/s) sediments vary considerably in depth along the profile, with the greatest depths 

near the southwestern end of the profile. The appreciable lateral variations in velocity 

below the 1500 m/s contour may suggest structural complexity below depths of about 20 

m.

 The approximately 575-m length of profile SL-6 allowed us to determine 

velocities to a maximum depth of approximately 75 m (Fig. 9). Near-surface velocities 

vary from about 800 to about to 1100 m/s in the upper 10 m, with higher near-surface 

velocities near meter 150 and between meters 400 and 450. High-velocity gradients in 

the upper 25 m are prominent, with maximum velocities of about 1800 m/s. The 

thickness of near-surface, low-velocity (< 1800 m/s) deposits does not vary significantly 

along the profile, although there is slightly greater thickness to the southwest. However, 

the depth of higher-velocity deposits (>1800 m/s) varies appreciably along the profile; 

high-velocity deposits are significantly deeper on the southwest end of the profile. 

Collectively, the velocity profiles suggest that low-velocity, unconsolidated, 

unsaturated sediments (< 1500 m/s) are relatively thin (< 5 m) near the San Francisco 

Bay, and they deepen (~40 m maximum) toward the center of the East Bay Plain (west of 

Washington Avenue). From near Washington Avenue eastward, the low-velocity 

sediments decrease in thickness toward the East Bay Hills to about 15 m or less. 

Velocities of 1500 m/s and higher follow a similar trend across the East Bay Plain, with 

lateral variations in velocity occurring abruptly. Such large changes in the velocity 

structure, occurring over relatively short distances, probably indicate tectonic disruption 

of sediments that may affect the ground-water-flow system. 

Seismic Reflection Data Processing 

In seismic-reflection data processing, we followed procedures similar to those 

outlined by Brouwer and Helbig (1998). Processing steps included geometry installation, 

independent trace editing, timing corrections, elevation static corrections, AGC, bandpass 

filtering, F-K filtering (or surgical muting), velocity analysis (from refractions, 

semblence, and borehole-velocity measurements), NMO correction, stretch muting, 

common-depth-point (CDP) stacking, post-stack AGC, post-stack bandpass filtering, and 

post-stack deconvolution. Principal parameters used in processing are shown in Table 2. 

For migrated images, we applied pre-stack Kirchoff depth migration after velocity 

analysis. 

In trace editing, noisy traces (due to cultural noises) or redundant traces (due to 

geometry) were removed from the shot gathers before stacking or migrating. Elevation 

statics, migration, and velocity analysis were accomplished, in part, using the 

tomographic velocity model from each profile. For velocities at depths in excess of those 

determined by the tomography velocity model, we used parabolic methods, and we 

inferred velocities based on lithologic logs from nearby wells and velocity-depth 

(pressure) relations (Carmichael, 1989). 
10

Table 2. Processing parameters for the San Leandro seismic profiles. 

Parameter SL-1 SL-2 SL-3 

CDP Spacing 2.3 – 2.5 m 1.7 – 2.5 m 2.3 – 2.5 m 

AGC 

 Prestack 

 Poststack 

500 ms 

100 ms 

500 ms 

100 ms 

500 ms 

100 ms 

Bandpass Filtering 

 Notch 

 Prestack 

 Poststack Low 

 Poststack High 

60, 120 Hz 

15-30-400-800 Hz 

15-30-400-800 Hz 

50-100-200-400 Hz 

60,120 Hz 

15-30-400-800 Hz 

15-30-400-800 Hz 

50-100-200-400 Hz 

60, 120 Hz 

15-30-200-400 Hz 

15-30-400-800 Hz 

50-100-200-400 Hz 

FK Filter (min-max 

veloc, min-max freq., kspace restrict.)

90m/s,800m/s,1Hz, 

600Hz 50%

90m/s,800m/s,1Hz, 

600Hz 50% 

90m/s,800m/s,1Hz, 

600Hz 50% 

Migration (freq., 

aperture, angle)

400Hz, 400m, 30deg 400Hz, 200m ,60deg 400Hz, 200m, 30deg 

Parameter SL-4 SL-5 SL-6 

CDP Spacing 2.4 – 2.6 m 2.4 – 2.6 m 2.4 – 2.8 m 

AGC 

 Prestack 

 Poststack 

500 ms 

100 ms 

500 ms 

100 ms 

500ms 

100ms 

Bandpass Filtering 

 Notch 

 Prestack 

 Poststack Low 

 Poststack High 

27 Hz 

15-30-400-800 Hz 

15-30-400-800 Hz 

50-100-200-400 Hz 

27 Hz 

15-30-400-800 Hz 

15-30-400-800 Hz 

50-100-200-400 Hz 

27 Hz 

15-30-400-800 Hz 

15-30-400-800 Hz 

50-100-200-400 Hz 

FK Filter (min-max 

veloc, min-max freq., kspace restrict.)

90m/s,800m/s,1Hz, 

600Hz 50%

90m/s,800m/s,1Hz, 

600Hz 50% 

90m/s,800m/s,1Hz, 

600 Hz 50% 

Migration(freq., 

aperture, angle)

400Hz, 200m, 30deg 400Hz, 200m, 30deg 400Hz, 100m, 30deg 

Seismic Reflection Images 

We developed seismic reflection images along each of the six profiles by stacking 

secondary arrivals from the same shot gathers used to obtain the velocity image. We 

present composite seismic reflection images of the East Bay Plain transect with relatively 

low frequencies (30-60-200-400 Hz; Figs. 10 and 17a), relatively high frequencies (50-

100-200-400 Hz; Fig. 11), and intermediate frequencies (25-50-400-800 Hz; Fig. 17b). 

The lower-frequency stacks image to greater depths, and the higher-frequency stacks 

more clearly resolve the upper few hundred meters of the subsurface. Thus, some of the 

images show structure at depths of 1500 m or more, and other images show details of the 

shallow (upper few hundred meters) subsurface. 

Reflection Images: Profiles SL-1 Through SL-6 

Numerous sub-horizontal reflections are imaged in the upper few hundred meters 

at relatively low frequencies (30-60-200-400 Hz) on the SL profiles (Fig. 10). These 

reflections correlate with sequences of sediments (sand, clay, and gravel) known to 

underlie the East Bay Plain (Izbicki et al., 2003), but at relatively low frequencies, thin 
11

layers may be averaged and represented on reflection images as a single reflector. 

Furthermore, the reflection images do not discriminate between individual layers of 

coarse or fine-grained sediment; instead, such layers are probably indicated as groups or 

sequences of sediments containing mixed textures. The lateral continuity of the more 

prominent reflectors suggests that the same or similar stratigraphic layers or groups of 

layers persist across the East Bay Plain from the bay to the Hayward fault, although these 

layers may differ laterally in content, such as grain size, degree of consolidation, and 

amount of tectonic disruption. Vertical offsets of stratigraphic layers and folding of 

layers in the reflection images suggest that the layers are disrupted at multiple locations 

along the SL profiles. Apparent disruptions in the stratigraphic layers occur along profile 

SL-1 between meters 200-400 and meters 1900-2800 and along much of profile SL-6. At 

these locations, the reflection image is distorted by diffractive energy. Such disruption is 

often associated with faults, but might result from the non-linear geometry of the seismic 

array in specific locations. Several observations argue against non-linear geometric 

distortion. First, the location and degree of disruption of the layers do not coincide with 

the location and degree of curvature of the seismic profile (see Figs. 2-8). Second, 

vertical offsets in the sedimentary layers persist beyond the areas of curvature of the 

seismic profile. Third, there are similar disruptions in the sedimentary layers in areas 

where the seismic array is linear. Fourth, the most disrupted reflectors coincide with 

zones of relatively low velocities; fault zones and low P-wave velocities have been well 

documented elsewhere (Mooney and Ginzburg, 1986; Catchings, 1999; Catchings et al., 

2002). On the basis of these observations, we suggest that the disrupted layers and the 

corresponding degraded reflection images result from vertical and horizontal offsets 

(faulting) and fracturing. The layered strata are disrupted in all depth ranges from the 

very near surface to at least the base of the layered strata, as inferred by the reflectivity 

pattern of the deeper seismic images. 

The thickness of layered strata is highly variable along the seismic transect. For 

example, within 1300 m of the San Francisco Bay (profile SL-1), strong reflections 

persist to depths in excess of 800 m, which is the greatest depth of such reflections 

observed along the seismic transect. Northeast of meter 1300 of profile SL-1, the deep 

(800 m) reflectors abruptly terminate, and from meter 1300 to about meter 1900 of 

profile SL-1, the sub-horizontal reflectors become progressively shallower (from ~800 to 

about 400 m deep) along an apparent series of faults. Because these reflectors do not dip 

significantly to the southwest, they probably were not deposited in an existing basin but 

were vertically offset after deposition. At depths of about 400 m and less, some of the 

more prominent reflectors are offset vertically at multiple locations along the seismic 

transect. 

Rocks underlying the layered strata are largely non-reflective, with depth to the 

top of the non-reflective rocks ranging from about 200 to 800 m along the East Bay Plain 

seismic transect. These non-reflective rocks are probably Franciscan basement rocks, but 

on the basis of reflectivity alone, we cannot be certain that some of the non-reflective 

rocks below 800m are not sediments. However, if the rocks below about 800 m depth are 

sediments, they are not sub-horizontally layered and probably dip at high angles to 

account for the lack of reflectivity. 

Higher-Frequency Stacks 

To provide more details of the upper 500 m along the seismic transect, we 

developed a higher-frequency (50-100-200-400 Hz) reflection image (Fig. 11). Because 

the frequency of the seismic wave determines, in part, which layers (minimum thickness) 

are imaged, higher-frequency seismic data can image thinner layers when all other 
12

parameters are the same. Whereas the lower-frequency seismic sections image a series of 

thin layers as a single reflector, multiple thin layers can be resolved with the higherfrequency data. The general formula (Dobrin and Savit, 1988) used to determine the 

minimum layer thickness needed to generate reflections is the one-quarter-wavelength 

criteria, where wavelength is: 

λ = v/f, where v = velocity (m/s), λ = wavelength (m), and f = frequency (Hz): 

and the radial width or length of the reflector is related to the Fresnel zone (W): 

ω = v/4 (sqrt(t/f), where t is time (sec), v=velocity (m/s): 

Only stratigraphic layers that are about one-fourth of λ and ω will likely generate 

reflections seen in figure 11. The minimum thickness of the reflectors varies with 

velocity, but assuming dominant frequencies of 100 Hz and average velocities of 1500 

m/s, as determined in the shallow subsurface along this transect, the shallow reflectors 

imaged in figure 11 are at least 4 m thick and 5 m long. Thus, layers thinner than about 4 

m and those with radii less than 5 m cannot be resolved with our data. Both the high- and 

low-frequency stacks show similar strata, but the high-frequency stack provides more 

detail, from which we correlate well logs and known stratigraphy. 

Well Logs 

Several wells with lithologic and/or electric borehole geophysical logs are located 

within 1 km of the seismic transect (Fig. 12). Most of these wells are several hundred 

meters from the seismic profile. To compare the borehole geophysical logs with the 

seismic images, we projected the wells perpendicularly onto the seismic profile (Figs. 12 

and 13). The stratigraphy should be generally consistent over distances of several 

hundred meters, although the exact stratigraphic sequence and depths to stratigraphic 

horizons beneath the seismic profile may differ somewhat from those determined in the 

wells because the wells and the seismic transect are not co-located. 

We identified 27 deep wells (>400 ft deep) along the seismic transect with 

available geophysical and/or lithologic logs. We plotted five geophysical logs from wells 

close to the seismic profile on the seismic sections. Wells 3S3W-14K12, 3S3W-13M4, 

and 3S3W-13D7 project perpendicularly to profile SL-1 at approximately meters 570, 

1010, and 1435, respectively, of the profile. Well 3S2W-7E1 projects to profile SL-2 at 

about meter 660, and well 3S2W-7G12 projects to profile SL-4 at about meter 145. Both 

spontaneous potential and resistivity logs are available for each well; however, for 

display purposes, we include only the short-normal resistivity logs on the seismic 

sections. We plotted seven lithologic logs from wells close to the seismic profile on the 

seismic sections. Wells 3S3W-14F1, 3S3W-14K2, 3S3W-14G2, 3S3W14J2, 3S3W12R1, project perpendicularly to profile SL-1 at meters 485, 525, 640, 840, 2570, 

respectively, of the profile. Well 3S3W-12H1 projects perpendicularly to the trend of the 

seismic profile at about meter 425 of profile SL-2, and well 3S2W-6R2 projects 

perpendicularly to profile SL-5 at about meter 175. 

The projected wells are not uniformly spaced along the seismic transect. There is 

only one nearby well along profile SL-5 and no wells near profile SL-6, making it more 

ambiguous to correlate known lithologies and these seismic images. Along profiles SL-1 

through SL-4, we correlate the seismic images with well-log data and infer lateral 

variations in sedimentary sequences that include major aquifers (Fig. 13). However, we 

emphasize that our interpretation is non-unique, particularly between the various seismic 

profiles and along profile SL-4, where the seismic image is degraded due to missing shot 

points. On the basis of our correlations, we suggest that the sedimentary sequences that 

contain the aquifer materials in some places are continuous across the East Bay Plain, but 
13

some layers are disrupted (vertically offset) in multiple locations. Although these 

sedimentary sequences appear continuous across much of the East Bay Plain, we 

emphasize that their compositions (grain size, lithology, etc.) may vary significantly 

along the seismic profile. These sedimentary sequences also vary in depth, but the 

general trend is for sequences to shallow to the northeast. Sub-horizontal reflectors below 

the Deep Aquifer along profiles SL-1 and SL-6 suggest that additional thick sedimentary 

sequences underlie the Deep aquifer, but the water-yielding potential of these sediments 

cannot be obtained from the seismic data. The deeper sedimentary sequences appear to 

be of limited lateral extent and do not extend across the entire East Bay Plain. The 

termination of sub-horizontal reflections along profile SL-6 suggests that most 

sedimentary sequences containing aquifers terminate west of the surface trace of the 

Hayward fault. 

Gravity Data and Models 

For this investigation, D.A. Ponce acquired gravity data along the East Bay Plain 

seismic transect (Table 3) that compliment a regional gravity data set published by Ponce 

(2001). Along the East Bay Plain seismic transect, gravity measurements were made 

every 40 m (every 8th seismic shot point) to help constrain the seismic observations (Fig. 

14). The raw data were reduced to provide the Bouguer (complete and simple) anomaly, 

which ranges from about –2.6 mgal near the Bay to about 20.5 mgal near the Hayward 

fault. The overall gravity field increases to the northeast along the seismic transect, but 

there are local anomalies superimposed on the regional trend, suggesting structural 

variations in the upper few kilometers. 

We developed a 2-D gravity model along the East Bay seismic transect (Figs. 15), 

and we compare our model with another gravity model (Ponce et al., 2003) adjacent to 

the East Bay Plain seismic transect (Figs. 14 and 16). We used densities similar to those 

of Ponce et al. (2003), with Franciscan basement, the San Leandro gabbro, and the basin 

sediments having densities of 2.67 g/cm3

, 2.48 g/cm3, and 2.2 g/cm3, respectively. Our 

model was developed using depths to basement inferred by the deepest sub-horizontal 

reflectors seen on the seismic transect (Fig. 16). Along the seismic transect, our gravity 

model assumes that variations in the gravity field are largely an indication of changes in 

the depth to Franciscan basement. Although lateral variations in the sedimentary section 

likely contribute to small anomalies in the gravity field, the largest anomalies in the 

gravity field are likely due to variations in the depth of basement rocks. Thus, our 

simplified model is probably indicative of the relative variation in the depth of basement 

rocks along the East Bay Plain seismic profile. 

Our gravity models suggests that Franciscan basement is about 900 m deep from 

the eastern shore of the SF Bay to about meter 1500 of the seismic profile, where it 

abruptly rises to about 525 m depth. From about meter 1500 to about meter 2200, 

basement rises along a series of steps to about 400 m depth. Along the remainder of the 

profile, basement varies in depth between about 200 and 400 m, except at the 

northeastern end of the profile, where basement sharply rises to within 50 m of the 

surface. Generally, the combined seismic/gravity model suggests a large vertical change 

in depth of basement near the bay, a small basin near the center of the transect, and a 

sharp rise in basement at the northeast end of the profile (Fig. 15). Our gravity model 

(based on seismic reflection images) is also consistent with basement depths modeled by 

Ponce et al. (2003) along an adjacent transect (Fig. 16), suggesting that the seismically 

imaged variations in basement structure are accurate. 
14

Table 3. Principal facts of gravity stations along the SL seismic transect. Latitudes and longitudes are based on 

the North American Datum 1927 (NAD27). CBA, complete Bouguer anomaly; Elev., elevation; FAA, free–air 

anomaly; ISO, isostatic anomaly; OG, observed gravity; SBA, simple Bouguer anomaly; TC, terrain correction. 

Station 

Name 

Location 

Lat ( 

Degrees 

Location 

Lon 

Degrees 

Elev 

Feet 

Observed 

Gravity 

mGal 

FAA 

mGal 

SBA 

mGal 

TC 

Inner 

mGal 

TC 

Outer 

mGal 

CBA 

mGal 

ISO 

mGal 

02SF3002 37 41.08 122 7.71 31.7 979954.48 -7.01 -8.09 0.28 1.08 -7.02 -7.88 

02SF3018 37 41.10 122 7.67 34.3 979954.69 -6.59 -7.76 0.18 0.98 -6.78 -7.61 

02SF3030 37 41.12 122 7.63 37.2 979954.58 -6.45 -7.72 0.18 0.99 -6.75 -7.55 

02SF3050 37 41.12 122 7.57 34.7 979954.99 -6.28 -7.46 0.18 1 -6.48 -7.24 

02SF3074 37 41.15 122 7.50 36.8 979955.19 -5.92 -7.18 0.18 1 -6.19 -6.91 

02SF3090 37 41.16 122 7.45 37.7 979955.35 -5.69 -6.98 0.3 1.12 -5.87 -6.56 

02SF3110 37 41.16 122 7.38 37.6 979955.66 -5.39 -6.68 0.3 1.13 -5.56 -6.21 

02SF3130 37 41.16 122 7.32 39.3 979955.89 -5 -6.34 0.3 1.13 -5.22 -5.83 

02SF3145 37 41.16 122 7.27 39.5 979956.17 -4.7 -6.05 0.3 1.13 -4.93 -5.51 

02SF4007 37 41.30 122 7.40 36.1 979956.5 -4.9 -6.13 0 0.84 -5.3 -5.93 

02SF4020 37 41.33 122 7.37 37.2 979956.7 -4.64 -5.91 0 0.85 -5.07 -5.68 

02SF4040 37 41.36 122 7.32 34.8 979957.28 -4.33 -5.51 0 0.86 -4.66 -5.23 

02SF4053 37 41.39 122 7.28 34.4 979957.56 -4.13 -5.3 0 0.87 -4.44 -4.98 

02SF4B01 37 41.45 122 7.23 33.6 979958.1 -3.75 -4.9 0 0.89 -4.02 -4.51 

02SF4B02 37 41.48 122 7.18 32.3 979958.53 -3.49 -4.59 0 0.9 -3.7 -4.15 

02SF4B03 37 41.55 122 7.18 29.8 979958.9 -3.46 -4.47 0 0.92 -3.56 -4 

02SF4B04 37 41.60 122 7.09 32.9 979959.25 -2.89 -4.01 0 0.94 -3.08 -3.45 

02SF5001 37 41.63 122 7.06 34.6 979959.28 -2.74 -3.92 0 0.94 -2.99 -3.34 

02SF5020 37 41.66 122 7.01 37.8 979959.33 -2.43 -3.72 0 0.95 -2.78 -3.09 

02SF5040 37 41.70 122 6.96 37.6 979959.63 -2.21 -3.49 0 0.97 -2.54 -2.81 

02SF5058 37 41.73 122 6.92 36.1 979959.98 -2.04 -3.28 0 0.98 -2.31 -2.54 

02SF6001 37 41.77 122 6.86 35.8 979959.86 -2.25 -3.47 0 1 -2.49 -2.68 

02SF6019 37 41.81 122 6.81 34.8 979960.37 -1.89 -3.08 0 1.02 -2.07 -2.21 

02SF6040 37 41.85 122 6.77 35.5 979960.49 -1.77 -2.98 0 1.04 -1.95 -2.06 

02SF6061 37 41.89 122 6.72 36.3 979960.49 -1.75 -2.99 0.01 1.07 -1.93 -1.99 

02SF6080 37 41.93 122 6.67 37.4 979960.52 -1.67 -2.95 0.03 1.12 -1.84 -1.86 

02SF6100 37 41.97 122 6.62 39.7 979960.5 -1.54 -2.89 0.07 1.18 -1.72 -1.7 

02SF6119 37 42.00 122 6.58 62.8 979959.27 -0.64 -2.78 0.07 1.15 -1.66 -1.61 

02SF6120 37 42.00 122 6.58 62.4 979959.19 -0.75 -2.88 0.07 1.15 -1.76 -1.71 

02SF6GPS 37 42.02 122 6.54 77 979958.63 0.03 -2.6 0.11 1.17 -1.46 -1.38 

Interpretation and Discussion 

 We interpret structures and stratigraphic relations along the SL seismic profiles on 

the basis of the combined reflection, refraction, well log, and gravity data. Many of these 

separate geophysical observations are consistent, leading to similar interpretations. 

Below, we discuss some of the more important issues related to earthquake hazards and 

ground-water-flow systems. 

Structure of the San Leandro Basin and East Bay Plain 

Consolidated basement rocks bound the aquifer system beneath the East Bay 

Plain. We interpret basement rocks to be the largely non-reflective rocks below depths of 

200 to 1000 m along the seismic transect (Figs. 10 and 17; Fig 18). These rocks are 

probably Franciscan and older rocks that are not well stratified, and thus do not generate 

strong reflective energy. The poorly reflective probable Franciscan basement rocks are 

located below 800 to 1000 m depth southwest of meter 1300 of profile SL-1. At about 

meter 1300 of profile SL-1, basement rocks are vertically offset, east side up, several 

hundred meters along a zone of faults (Figs. 17 and 18). From about meter 1300 to about 

meter 2000, basement rocks rise along a series of faults to depths of about 400 m below 

land surface. The gravity anomaly along the southwestern 1300 m of profile SL-1 can be 

interpreted similarly, whereby basement abruptly rises by hundreds of meters over 

relatively short distances (Fig. 18). As observed within many strike-slip fault zones, there 

is greater vertical offset on some faults than other faults within a fault zone. From meter 

2000 to about meter 3100, basement varies only slightly in depth (~50 m), but from about 

meter 3100 to about meter 4000, basement deepens by about 100 m. Although the 
15

reflectors are not as well imaged along this segment of the transect as areas to the west, 

vertically offset reflectors suggest that basement deepens along one or more faults. 

Between meters 4000 and 4700 basement abruptly rises about 100-200 m to a depth of 

about 400 m. This also probably occurs along one or more faults. Between meter 5000 

and to about meter 6000, basement rises to about 250 m depth, but because of large gaps 

in the seismic transect, we do not know if additional faults are present in this part of the 

transect. From about meter 6200 to the end of the seismic profile, basement abruptly 

rises to the near-surface along strands of the Hayward fault. 

On the basis of the gravity and reflectivity patterns observed, we conclude that the 

deepest onshore part of the San Leandro Basin is about 800 to 900 m below the ground 

surface (bgs), and it extends northeastward about 1.4 km inland. Maximum depths of 

approximately 800 m for sub-horizontally layered sediments within the San Leandro 

Basin are consistent with observations by Marlow et al. (1999), who also imaged subhorizontal reflectors to depths of about 800 m near the center of the San Leandro Basin 

beneath the San Francisco Bay. However, on the basis of gravity modeling, Marlow et 

al. (1999) noted that relatively low-density (2.12 to 2.25 g/cm3

) rocks may extend to as 

much as 1.5 km depth. Although we cannot rule out the possibility that additional 

sediments underlie the sub-horizontal strata within the San Leandro Basin, the reflectivity 

pattern below 800-900 m near the bay is consistent with shallow-depth basement rocks 

imaged farther northeast along the transect. Furthermore, gravity modeling is consistent 

with shallow depths to basement on the northeast end of the profile and our imaged depth 

near the bay of 800-900 m. 

Evidence for Faults Underlying the East Bay Plain 

In several of the above sections of this report, we have highlighted evidence that 

infers the existence of faults beneath the East Bay Plain. In this section, we discuss the 

cumulative evidence. The principal evidence for the existence of buried faults beneath 

the East Bay Plain are the high-resolution reflection images, which show several zones 

along the transect where reflectors are vertically offset (Figs. 11, 19, 20, 21). We cannot 

exclude the possibility that some of the vertically offset reflections are artifacts related to 

non-linearity of the seismic profiles, but the combined velocity, gravity, and reflection 

data strongly suggest that the vertically offset reflectors are buried faults. Only selected 

individual faults are shown on figures 18 and 22. Further study likely may reveal 

additional faults. For purposes of discussion, we refer to the zones of vertically offset 

reflections as fault zones. 

Fault zones are known to cause P-wave velocity anomalies, whereby lower 

seismic velocities occur within the fault zones relative to adjacent areas (Aki and Lee, 

1976; Mooney and Luetgert, 1982; Catchings et al., 2002). Within the depth ranges of 

our seismic velocity measurements, we observe similar velocity anomalies within each of 

the probable near-surface East Bay Plain fault zones. Along profile SL-1, there are 

distinct low-velocity zones centered near meters 250 and 2250, and these low-velocity 

zones correlate with zones of near-surface, vertically offset reflections (Figs. 11 and 19). 

Similar, but less prominent low-velocity zones are observed along and between various 

profiles across the East Bay Plain. 

The velocity data further suggest that several of the areas with vertically offset 

reflectors are zones of faulting by virtue of a relationship between the relative depth of 

fully saturated sediments and seismic velocity. As discussed above, unconsolidated, 

water-saturated sediments have minimum P-wave velocities of 1500 m/s (Nur, 1982; 

Schon, 1996), and lateral variations in the 1500 m/s velocity contours can be used to infer 

the relative depth of these sediments (Catchings et al.,1999; 2000a; Gandhok et al., 
16

1999). Along the East Bay Plain seismic transect, the depth to the 1500 m/s velocity 

contour (saturated sediments) increases within and southwest of the major near-surface 

fault zones (as inferred by vertically offset reflectors) (Fig. 19). Conversely, the saturated 

sediments are most shallow northeast of the near-surface fault zones. Ground-water 

flows from the northeast to the southwest across the East Bay Plain (San Francisco Bay 

Regional Water Quality Control Board, 2004). Thus, the inferred lateral variation in 

relative depth to the ground-water table, whereby it is shallower to the northeast and 

deepens to the southwest of fault zones, is expected if the offset reflectors are groundwater barriers caused by faulting (Fig. 19). Mechanical disruption of sediments in fault 

zones reduces seismic velocity in a manner consistent with the seismic velocity profiles. 

Available ground-water-level data are areal1y too sparse and temporally too widely 

spread to definitively confirm or refute interpretations of water table depth derived from 

the seismic velocity data. 

Gravity modeling is consistent with the seismic reflection image, whereby the 

gravity model infers near-vertical offsets in stratigraphic layers, especially near the 

northern end of the San Leandro Basin. These near-vertical offsets in stratigraphy suggest 

a number of fault strands underlie the East Bay Plain between the San Francisco Bay and 

the Hayward fault. Additional seismic profiling and paleoseismic trenching are needed 

to confirm the imaged fault zones, but the cumulative reflection, velocity, and gravity 

data presented in this study strongly suggest multiple fault strands underlie the East Bay 

Plain. 

Length of Faults 

Although the cumulative data suggest multiple fault strands underlie the East Bay 

Plain, the lengths of these faults are unknown. Fault length is important for earthquake 

hazard assessment because fault length is directly related to the maximum magnitude 

earthquake the faults can generate. Sparsely spaced earthquake hypocenters recorded 

between 1984 and 2004 (ANSS, 2004; Zoback and Olson, 1995; Simpson et al., 2004) 

are consistent with sub-alluvial faults that may extend from the southern Santa Clara 

Valley to the northern part of the San Francisco Bay. On the basis of vertically offset 

reflectors observed along the East Bay Plain seismic transect, we suggest that the fault 

zone bounding the San Leandro Basin on the northeast at about meter 1300 of the SL-1 

profile may be the most laterally extensive of the East Bay Plain faults, with the 

exception of the Hayward fault. The lack of significant southwestward dipping strata 

within and near the northeastern end of the San Leandro Basin suggests that the 

northeastern end of the basin formed along a zone of faults with a significant (~500 m) 

component of vertical movement rather than a uniformly down-warping central basin as 

suggested by Marlow et al. (1999). Such a large vertical offset suggests that the fault 

may be laterally extensive, and a growing body of geophysical evidence (Catchings et al., 

in prep.) suggests that the bounding fault may be an extension of the Silver Creek Fault 

zone. The Silver Creek fault zone has been mapped and imaged farther south within the 

Santa Clara Valley (Bortugno et al., 1991; Catchings et al., 2000b; R. Williams, Pers. 

Comm, 2005), and older ground-water and gravity data suggest that the fault extends as 

far north as Union City (CDWR, 1967). For purposes of discussion in the report, we refer 

to the fault bounding the San Leandro Basin as the East Bay fault zone, which would be 

more than 60 km long if it is contiguous with the Silver Creek fault zone. 
17

Recency and Extent of Faulting Across the East Bay Plain 

If active, the East Bay fault zone may be capable of generating earthquakes with 

magnitudes comparable to or larger than those of the Hayward fault, based on 

comparison of the lengths of the faults. The shallow depths to which the East Bay fault 

zone offsets strata along profile SL-1 suggests that the fault has been active relatively 

recently (Figs. 11, 20, and 21). Furthermore, low-level seismicity in the vicinity of the 

imaged faults (Zoback and Olson, 1995; Simpson et al., 2004) indicates that the faults are 

probably active (Fig. 22). At shallow depths (upper 400 m), vertically offset strata along 

the seismic transect indicate that other faults underlie the East Bay Plain between the East 

Bay and Hayward faults; we refer to these faults as middle faults. Although the middle 

faults may be separate faults, they may also be strands that merge with either the East 

Bay or Hayward fault zones at depth. Earthquake hypocenters indicate that some of the 

faults are deep seated (Simpson et al., 2004) and are unrelated to the Hayward fault above 

Moho depths. 

Aquifers 

Izbicki et al. (2003) list four principal zones in the East Bay Plain ground-water 

basin that may be time correlative with aquifer sediments in the Niles Cone ground-water 

basin, the Newark (9-40 m bgs), Centerville (36 to 67m bgs), Fremont (73 to 122 m bgs), 

and the Deep aquifers (152 to 198 m bgs). From comparisons among the seismic images 

and borehole electric and lithologic logs acquired near the seismic transect, the Deep 

aquifer correlates well with specific reflectors, but the Newark, Fremont, and Centerville 

aquifers do not stand out prominently on some electric logs, making their exact depth 

range poorly determined (Fig. 13). As such, there is some ambiguity in correlating the 

reflection horizons on the seismic image with specific layers of the Newark, Centerville, 

and Fremont aquifers. Many investigators have been unable to trace individual 

permeable beds of the Newark, Centerville, and Fremont aquifers between boreholes and 

wells in the East Bay Plain (Izbicki et al., 2003). In this report, we do not specifically 

identify the Newark, Centerville and Fremont aquifers; rather, we identify a series of 

reflectors that encompasses the depth ranges believed to include discontinuous permeable 

lenses of sediment that are time-correlative with the Newark, and the Centerville/Fremont 

aquifers as defined in the Niles Cone ground-water basin to the south. Partly 

consolidated sedimentary deposits having low porosity and low permeability are believed 

to underlie the major aquifers in the study area (Marlow et al., 1999), but we have not 

attempted to identify individual stratigraphic layers or permeable beds within the 

sediments underlying the Deep aquifer. 

Near-coincident logged wells and the seismic transect show that aquifer zones 

often correlate with specific groups of reflectors. Some of these reflectors can be traced 

across the entire seismic transect, suggesting that the stratigraphic horizons that often 

contain permeable deposits are continuous across the East Bay Plain. The correlation 

between well logs and the reflection profile is best for the Deep aquifer, the thickest and 

most persistent permeable horizon of permeable sediments in the East Bay Plain (Figs. 13 

and 21). A group of reflectors that correlate with the Deep aquifer varies in thickness 

across the East Bay Plain but is thickest near the SF Bay. Short-normal resistivity logs 

show that some layers of the Deep aquifer are consistently resistive, suggesting that they 

consist of clean, fresh-water–bearing sand and gravel layers. To the northeast, near San 

Leandro High School, there may be fewer coarse-grained layers within the Deep aquifer 

sediments. 
18

The hydraulic properties and quality of water within sediments that are strong 

reflectors beneath the Deep aquifer, seen most prominently southwest from meter 1300 of 

profile SL-1 and along profile SL-6, have not been determined. Historical well records 

indicate that several wells southwest from meter 1300 of profile SL-1 were drilled deeper 

than the bottom Deep aquifer in the early 1900s but well records do not identify 

perforated intervals of casing or water production rates for these deep wells. A downwell television scan (Michael Burke, Fugro West, written communication, 1997) of well 

3S3W-14K2, drilled 993 feet deep in 1919, indicated that the steel well casing was 

perforated at depths below the Deep aquifer but other historical information is 

unavailable. Because well 14K2 is filled with sediment to 813 feet below land surface 

and much of the steel casing is encrusted with scale, the identification of perforated 

intervals by TV scan or hydraulic testing to determine hydraulic characteristics of 

sediments underlying the Deep aquifer are infeasible. If the reflectors beneath the Deep 

aquifer are Pliocene sediments (as Marlow and others (1999) suggest underlie Pleistocene 

deposits in the San Leandro basin) or if the reflectors are partly consolidated rocks (as 

encountered by deep wells near Bay Farm Island, north from the study area (Izbicki and 

others, 2003)), it is unlikely that the reflectors are aquifer zones that might be developed 

for water supply or artificial storage of water. 

East Bay Plain Faults, Ground-Water Flow, and Infrastructure 

In this report, we note several important features of the subsurface structure and 

stratigraphy that may impact ground-water flow and infrastructure across the East Bay 

Plain. 

Hydraulic head data (Izbicki et al., 2003) indicate that ground water generally 

flows through shallow sediments from the hills on the east to the bay on the west. If the 

faults imaged on the reflection profile trend parallel to the Hayward fault, as expected, 

they may retard the flow of ground water toward the bay to some extent. Available 

ground-water-level data are areally too sparse to definitively confirm or refute 

interpretations of water table depth derived from the seismic velocity data. 

Sedimentary units containing the Newark, Centerville/Fremont, and Deep aquifers 

are probably all affected by the fault zones, as their thickness and depth below ground 

surface appear to vary across the fault zones. If the faults hydraulically restrict westerly 

ground-water flow, they may partly compartmentalize the aquifer system, causing the 

performance of ground-water facilities to vary from operations as designed. A better 

understanding of the 3-dimensional aquifer structure and hydraulic continuity is needed 

to assess the effect of faults within the East Bay Plain. 

Movement on faults underlying the East Bay Plain may restrict lateral groundwater flow. During future earthquakes, vertical movements of just a few meters may 

offset aquifers enough to affect flow across the fault zones. Similarly, such movements 

may hamper water-utility infrastructure such as pipelines. A more complete 

understanding of the locations and orientations of active faults within the East Bay Plain 

may allow for improvements before future damaging earthquakes. Such planning was 

implemented along the Alaska oil pipeline where it crossed four major fault zones 

identified from scientific investigations conducted in the 1970’s. During the November 

3, 2002 M. 7.9 Denali earthquake (Eberhart-Phillips et al., 2003), nearly 4 m of 

horizontal and 0.75 m of vertical offset occurred across the fault, but because of special 

engineering along the fault zones, there was no disruptive damage to the pipeline (Cluff 

and Slemmons, 2002). Similar engineering could be implemented across the East Bay 

Plain faults if their locations throughout the East Bay were determined. 
19

Suggestions for Future Work 

Movement on fault zones beneath the East Bay Plain could affect ground-water-flow 

directions. A concerted effort to locate active faults beneath the East Bay Plain should be 

undertaken so that production wells can be strategically placed to minimize disruptions 

from future earthquakes on the subsurface faults. A combination of strategically placed 

water-level observation wells, high-resolution seismic imaging, INSAR imaging, and 

paleoseismological trenching may be a useful approach. 

Acknowledgements: 

We thank the East Bay Municipal Utility District (EBMUD) for providing partial funding 

for this investigation and assisting with access. We also thank Alameda County, the City 

of San Leandro, San Leandro High School, and EBMUD for permits and access. We 

thank Coyn Criley, Coye Criley, Dave Cornwell, Shane Detweiler, Joel Fassbinder, Sam 

Gudino, Wendy Hauso, Amy Padovani, A.S.S.S.R.S. Prashad, Friedericke Schmitz, 

Camgna Thach, and V Shridher for field assistance. Thanks to Jim Lienkamper and Jack 

Boatwright, who provided critical reviews. We thank Bob Bainer of Lawrence 

Livermore National Laboratory for providing seismic sources along 163rd Avenue in San 

Leandro, and we thank IRIS-PASSCAL for providing one of the multichannel 

seismographs used to record the data. We thank Kelly McPherson and Tim Dawson, 

USGS, for surveying the locations of shot points and sensor arrays. 

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23

Figures 

Figure 1. Map of the San Francisco Bay area, with major fault zones and cities of the East 

Bay Plain and Niles Cone areas. The location of figure 2 and the general location of the 

seismic transect discussed in the report are shown by the red box. Various cities within 

the East Bay Plain are listed: A=Alameda, F=Fremont, H=Hayward, N=Newark, O= 

Oakland, SL= San Lorenzo, SLe=San Leandro, UC=Union City. Major roads are shown 

in gray, and major fault zones are shown in yellow. 

Figure 2. Parts of the USGS 7.5-minute San Leandro and Hayward topographic maps 

showing the locations of the East Bay Plain (SL) seismic transect. Individual segments 

of the transect are labeled SL-1 through SL-6. The dashed line shows the general 

placement of the seismic arrays. 

Figure 3. (a) Geophone elevation along seismic profile SL-1. Elevation is relative to the 

topographically lowest geophone along the profile. (b) Variation of geophones from a 

line that connects the first and last geophone along the profile. (c) Shot point elevation 

along seismic profile SL-1. Elevation is relative to the topographically lowest shot point 

along the profile. (d) Variation of shot points from a line connecting the first and last shot 

point along the profile. (e) Fold as a function of distance along the SL-1 seismic profile. 

Figure 4. (a) Geophone elevation along seismic profile SL-2. Elevation is relative to the 

topographically lowest shot point along the profile. (b) Variation of geophones from a 

line that connects the first and last geophone along the profile. (c) Shot point elevation 

along seismic profile SL-2. Elevation is relative to the topographically lowest shot point 

along the profile. (d) Variation of geophones from a line connecting the first and last 

shot point along the profile. (e) Fold as a function of distance along the SL-2 seismic 

profile. 

Figure 5. (a) Geophone elevation along seismic profile SL-3. Elevation is relative to the 

topographically lowest shot point along the profile. (b) Variation of geophones from a 

line that connects the first and last geophone along the profile. (c) Shot point elevation 

along seismic profile SL-3. Elevation is relative to the topographically lowest shot point 

along the profile. (d)Variation of geophones from a line connecting the first and last shot 

point along the profile. (e) Fold as a function of distance along the SL-3 seismic profile. 
24

Figure 6. (a) Geophone elevation along seismic profile SL-4. Elevation is relative to the 

topographically lowest shot point along the profile. (b) Variation of geophones from a 

line that connects the first and last geophone along the profile. (c) Shot point elevation 

along seismic profile SL-4. Elevation is relative to the topographically lowest shot point 

along the profile. (d) Variation of geophones from a line connecting the first and last 

shot point along the profile. (e) Fold as a function of distance along the SL-4 seismic 

profile. 

Figure 7. (a) Geophone elevation along seismic profile SL-5. Elevation is relative to the 

topographically lowest shot point along the profile. (b) Variation of geophones from a 

line that connects the first and last geophone along the profile. (c) Shot point elevation 

along seismic profile SL-5. Elevation is relative to the topographically lowest shot point 

along the profile. (d) Variation of geophones from a line connecting the first and last 

shot point along the profile. (e) Fold as a function of distance along the SL-5 seismic 

profile. 

Figure 8. (a) Geophone elevation along seismic profile SL-6. Elevation is relative to the 

topographically lowest shot point along the profile. (b) Variation of geophones from a 

line that connects the first and last geophone along the profile. (c) Shot point elevation 

along seismic profile SL-6. Elevation is relative to the topographically lowest shot point 

along the profile. (d) Variation of geophones from a line connecting the first and last 

shot point along the profile. (e) Fold as a function of distance along the SL-6 seismic 

profile. 

Figure 9. P-wave seismic velocity model along the East Bay Plain seismic (SL) transect 

with various landmarks shown. Cumulative distance is shown along the bottom. Note that 

in profile view, profiles SL-3 and SL-4 overlap (see fig. 2), but lateral distance between 

the beginning and end of SL-3 and SL-4, respectively, is several hundred meters. 

Distance along individual profiles (see figure 2) are shown above the figure. Velocities 

are in m/s, and depth and distance are in meters. Depth is relative to the topographically 

lowest geophone along each seismic profile. The 1500 m/s contour, which probably 

shows lateral variations in the relative depth to continuously saturated sediments (water 

depths), is shown in white. Because of smoothing in the velocity model, absolute depths 

of the water table may not be accurate. 

Figure 10. A relatively low-frequency (30-60-200-400 Hz) composite seismic reflection 

image of the upper 1500 m along the East Bay Plain seismic transect. Stacking fold, 

elevation, and various landmarks are shown above the figure. Each seismic profile, SL-1 

through SL-6, is shown relative to its distance from the southeastern-most geophone 

along the profile. However, distance between profiles SL-3 and SL4 includes lateral 

distance between the ends of the profiles. Depth and distance are in meters. Depth is 

relative to the lowest point along each seismic profile. 
25

Figure 11. A relatively high-frequency (50-100-200-400 Hz) composite seismic 

reflection image along the East Bay Plain, plotted as in figure 10. Only the upper 500 m 

are shown along the profile because the higher frequencies generally limit the depth of 

reflection imaging. The locations of various wells with available geophysical and 

lithologic logs and various landmarks are shown above the figure. 

Figure 12. Photograph of the area encompassing the East Bay Plain seismic transect and 

selected nearby wells. Seismic profiles are shown in red, and perpendicular projections of 

the wells to the seismic profile are shown in yellow. The base map is modified from the 

USGS San Leandro and Hayward, California 7.5-minute orthophoto maps. 

Figure 13. Seismic image from figure 11 with short-normal resistivity logs (red) and 

simplified lithologic logs (multi-colored) projected onto the seismic image at 

perpendicular distances. Sedimentary layers that contain aquifers in some places are 

shown in blue. Lateral extensions of the aquifer-bearing layers are inferred based on 

laterally continuous or nearly continuous reflectors. Continuity of reflectors between the 

profiles is only inferred. 

Figure 14. Topographic map of the central East Bay Plain, showing the general location 

of the East Bay Plain (SL) seismic transect, along which our gravity model is constructed 

(orange), and the profile along which the model (profile C-C”; in black) of Ponce et al., 

(2003) is constructed. The yellow dots show earthquake epicenters with size proportional 

to magnitude. The red line shows the approximate surface trace of the Hayward fault 

(from Ponce et al., 2003). 

Figure 15. (a) Observed (blue) and calculated (red) Bouguer gravity anomaly along the 

East Bay Plain seismic transect. (b) Gravity model based on seismic-reflectiondetermined depths to basement rocks (green) and the best fit to the Bouguer gravity data. 

Density (in parentheses) is in grams per cubic centimeter. Because distance between 

profiles SL-3 and SL-4 is mostly lateral distance, basement depths are extrapolated in that 

area. 
26

Figure 16. Observed (black) and calculated (red) (a) magnetic and (b) gravity anomaly 

along profile C-C' (see figure 14). (c) Gravity and magnetic models along profile C-C' 

(from Ponce et al., 2003). Geologic symbols: Qa, Quaternary alluvium and related lowdensity materials; Tn, Neroly Sandstone; Ts, undifferentiated Tertiary sedimentary rocks; 

KJF, Franciscan Complex; Kjm, Joaquin Miller Fm; Kjk, Knoxville Fm; Ko, Oakland 

conglomerate; Ks, undifferentiated Cretaceous sedimentary rocks; Jb, basalt; Jgb, gabbro; 

Jpb, pillow basalt; jsv, quartz keratophyre; sp, serpentinite; sp-px, pyroxenite. 

Geographic and other symbols: SF Bay, San Francisco bay; SL Res., San Leandro 

reservoir, Inverted red triangles, recent trace of Hayward Fault (HF) and Chabot Fault 

(CF); D, density in grams/cubic centimeter; S, susceptibility in CGS units; Drill-hole 

symbol, thickness of offshore sedimentary basin from seismic and gravity data (Marlow 

et al., 1999); +, seismicity from relocated hypocenters using double-difference relocation 

method within 5 km of the profile (Waldhauser and Ellsworth, 2000; 2002). The red 

rectangle shows the approximate location of the East Bay Plain seismic transect (2 km 

depth). 

Figure 17. (a) Composite seismic image (30-60-200-400 Hz) from figure 10 with 

interpreted layer sequences (blue) containing ground-water aquifers, electric and 

lithologic well logs, faults (red), and basement topography, as modeled with our SL 

gravity model (yellow) and the model of Ponce et al. (2003) (orange) north of the SL 

seismic profile. The basement topography modeled by Ponce et al. (2003) is extrapolated 

(dashed line) along segments of the SL profile that do not trend northwestward. 

Figure 17 (b) Seismic reflection image along profile SL-1, plotted with lower frequencies 

(25-50-400-800 Hz) than in figure 17a. Gravity-inferred basement topography (orange – 

Ponce et al., 2003; yellow = SL gravity model) is superimposed on the reflection image. 

Figure 18. Interpretative cross section (including wells, electric logs, sedimentary 

sequences containing aquifers, faults, etc), with basement as inferred from the SL gravity 

model (black-green). Basement as inferred from the model of Ponce et al. (2003) north of 

the SL profile is shown in orange. The basement topography modeled by Ponce et al. 

(2003) is extrapolated (dashed line) along segments of the SL profile that does not trend 

northwestward. Areas along the East Bay transect with apparent shallow-depth faults are 

outlined in red above the interpretative cross section. 

Figure 19. (a) Velocity model (from figure 9) along the East Bay Plain seismic transect, 

with the 1500 m/s velocity contour (lateral variation in the relative depth of continuously 

saturated sediments) shown in white (b) Relatively high-frequency (50-100-200-400 Hz) 

seismic reflection image (from figure 11) with borehole electric logs and interpretative 

sedimentary sequences that contain aquifers in places. Note that low-velocity zones 

correlate with apparent zones of near-surface (upper 80 m) faulting. 
27

Figure 20. A relatively low-frequency (25-50-400-800 Hz) migrated seismic reflection 

image along profile SL-1. Note the numerous vertically offset layers, particularly those 

between meters 200 and 400 and meters 1600 and 2500. The red arrows are located over 

two zones of faulting that are most apparent at about 400 m depth. 

Figure 21. A relatively intermediate-frequency (35-70-200-400 Hz) migrated seismic 

reflection image of all profiles along the East Bay Plain seismic transect. Borehole 

resistivity and lithologic well logs and interpreted sedimentary sequences that sometimes 

contain aquifers are shown on the seismic section. The pink line in the upper 50 m shows 

the 1500 m/s velocity contour along the seismic transect (interpolated between seismic 

profiles) as determined from the SL velocity model (fig. 9). 

Figure 22. Seismic reflection image (from figure 17b) along profile SL-1 with 

hypocenters of earthquakes within 3 km of the profile. Earthquake locations are from the 

Northern California Catalog (ANSS, 2004). Note that the hypocenters from nearby small 

earthquakes largely align with the northeastern edge of the San Leandro Basin. 

Earthquakes beyond 3 km from the SL profile are shown in figure 14. 
28

Appendixes 

Appendix A. 

Coordinates of the beginning and end of each profile in latitude and longitude and in UTM coordinates. 

LINE LAT LONG Easting Northing 

Start SL1 37:40.1174 -122:09.8860 573661 4169377 

End SL1 37:41.0649 -122:08.3701 575873 4171150 

Start SL2 37:41.0984 -122:08.3085 575963 4171212 

End SL2 37:41.0719 -122:07.8083 576698 4171170 

Start SL3 37:41.0727 -122:07.7788 576742 4171172 

End SL3 37:41.1566 -122:07.3337 577394 4171333 

Start SL4 37:41.2864 -122:07.4765 577182 4171571 

End SL4 37:41.3865 -122:07.3429 577377 4171758 

Start SL5 37:41.6257 -122:07.1288 577687 4172203 

End SL5 37:41.7245 -122:06.9805 577903 4172388 

Start SL6 37:41.7864 -122:06.9004 578020 4172504 

End SL6 37:42.0097 -122:06.6289 578415 4172920 

Appendix B 

Distances and elevations along East Bay Seismic Profile 1 (SL-1). 

Measurements are relative to the first receiver point at the west end of Profile SL-1. 

Station No. Receiver Dist. (m) Receiver Elev. 

(m) 

Station No. Shot Dist. (m) Shot Elev. (m) 

1 0 0 

2 3.4 0.04 

3 7.36 0.06 

4 10.81 0.13 

5 14.71 0.13 

6 19.56 0.17 

7 24.46 0.17 

8 29.21 0.31 

9 34.16 0.53 9 34.06 0.46 

10 39.01 0.59 10 38.76 0.59 

11 43.96 0.57 11 43.81 0.59 

12 48.87 0.63 12 48.66 0.62 

13 53.77 0.74 13 53.47 0.74 

14 58.62 0.74 14 58.37 0.73 

15 63.52 0.67 15 63.22 0.68 

16 68.37 0.74 16 68.17 0.77 

17 73.52 0.78 17 73.22 0.82 

18 78.27 0.81 18 78.02 0.82 

19 83.02 0.82 19 82.92 0.84 

20 88.07 0.81 20 87.87 0.87 

21 92.87 0.86 21 92.62 0.9 

22 97.72 0.87 22 97.47 0.91 

23 102.67 0.9 23 102.42 0.9 

24 107.67 0.89 24 107.38 0.88 

25 112.53 0.9 25 112.22 0.86 

26 117.37 0.89 26 117.08 0.86 

27 122.28 0.9 27 121.87 0.9 

28 127.18 0.96 28 126.92 0.99 

29 132.12 0.97 29 131.83 0.96 

30 136.88 1.01 30 136.78 1.02 

31 141.78 1.02 31 141.58 1 

32 146.63 0.99 32 146.53 1.01 
29

33 151.58 0.95 33 151.33 0.97 

34 156.43 0.95 34 156.28 0.97 

35 161.33 0.97 35 161.03 1 

36 166.18 0.9 36 165.93 0.95 

37 171.03 0.95 37 170.93 0.95 

38 175.98 0.95 38 175.68 1 

39 180.88 0.96 39 180.58 0.97 

40 185.69 0.98 40 185.54 1.05 

41 190.58 1.03 41 190.39 1.08 

42 195.43 1.01 42 195.18 1.05 

43 200.33 1.02 43 200.29 1.03 

44 205.18 1.05 

45 210.09 1.09 45 209.93 1.06 

46 215.08 1.09 46 214.99 1.04 

47 220.04 1.16 47 220.04 1.13 

48 224.99 1.2 48 224.94 1.18 

49 229.94 1.28 49 230.04 1.25 

50 234.99 1.25 50 235.14 1.29 

51 239.99 1.13 51 239.94 1.19 

52 244.94 1.06 52 244.84 1.17 

53 249.99 1.12 53 249.93 1.18 

54 254.94 1.09 54 254.84 1.21 

55 259.99 1.09 55 260.14 1.17 

56 264.89 1.11 56 264.89 1.11 

57 269.98 1.22 57 269.79 1.17 

58 274.83 1.24 58 274.94 1.18 

59 279.98 1.18 59 279.83 1.15 

60 284.89 1.13 60 285.03 1.07 

61 289.99 1.21 61 289.88 1.19 

62 294.88 1.2 62 294.79 1.22 

63 299.99 1.16 63 299.64 1.26 

64 305.14 1.26 64 304.84 1.33 

65 309.89 1.18 65 309.84 1.16 

66 314.84 1.29 66 314.89 1.29 

67 319.89 1.23 67 319.98 1.31 

68 324.93 1.25 68 324.89 1.29 

69 329.94 1.37 69 330.13 1.36 

70 334.48 1.34 

71 339.84 1.31 71 339.83 1.41 

72 344.84 1.29 72 344.89 1.29 

73 349.84 1.32 

74 354.84 1.27 74 354.79 1.3 

75 359.84 1.37 75 359.79 1.35 

76 364.78 1.34 76 364.98 1.31 

77 369.78 1.32 

78 374.78 1.35 78 374.89 1.3 

79 379.84 1.3 79 379.89 1.35 

80 384.84 1.3 80 384.83 1.36 

81 389.94 1.4 81 389.68 1.33 

82 394.89 1.4 82 394.89 1.29 

83 399.89 1.36 83 400.08 1.32 

84 404.84 1.43 84 404.99 1.31 

85 409.84 1.43 85 409.83 1.4 

86 414.78 1.46 86 414.83 1.4 

87 419.89 1.41 

88 424.84 1.56 88 424.89 1.53 

89 429.78 1.51 89 429.89 1.51 

90 434.89 1.51 90 434.89 1.45 

91 440.03 1.48 

92 444.74 1.37 92 444.89 1.36 

93 449.93 1.35 93 449.83 1.34 

94 454.93 1.4 

95 459.64 1.33 95 459.64 1.35 

96 464.59 1.32 96 464.84 1.38 

97 469.84 1.35 97 469.73 1.35 

98 474.84 1.29 98 474.73 1.44 

99 479.74 1.35 99 479.84 1.44 

100 484.89 1.32 100 484.64 1.37 

101 489.89 1.41 101 489.58 1.49 

102 494.89 1.44 102 494.73 1.47 
30

103 499.83 1.35 103 499.94 1.37 

104 504.79 1.43 

105 509.79 1.38 105 509.84 1.41 

106 514.68 1.34 106 514.64 1.32 

107 519.83 1.35 107 519.73 1.36 

108 524.78 1.39 108 524.83 1.38 

109 529.78 1.4 

110 534.74 1.43 110 534.74 1.38 

111 539.84 1.35 111 539.69 1.36 

112 544.84 1.38 112 544.69 1.35 

113 549.79 1.45 113 549.69 1.39 

114 554.73 1.48 114 554.69 1.43 

115 559.88 1.6 115 559.74 1.51 

116 564.58 1.5 116 564.74 1.49 

117 569.88 1.5 117 569.69 1.46 

118 574.84 1.6 118 574.84 1.56 

119 579.79 1.59 

120 584.88 1.64 120 584.84 1.55 

121 589.88 1.63 121 589.69 1.6 

122 594.53 1.66 122 594.64 1.67 

123 599.83 1.7 123 599.74 1.69 

124 604.69 1.73 124 604.79 1.71 

125 609.74 1.66 125 609.69 1.6 

126 614.84 1.69 126 614.64 1.74 

127 619.79 1.72 127 619.74 1.67 

128 624.79 1.7 

129 629.83 1.82 129 629.64 1.71 

130 634.83 1.61 130 634.74 1.36 

131 639.83 1.65 131 639.79 1.54 

132 644.88 1.57 132 644.89 1.43 

133 649.88 1.43 133 649.94 1.38 

134 654.83 1.52 134 654.79 1.42 

135 659.79 1.56 135 659.79 1.52 

136 664.84 1.72 136 664.79 1.8 

137 669.74 1.77 137 669.68 1.82 

138 674.79 1.66 138 674.79 1.71 

139 679.94 1.69 139 679.79 1.7 

140 684.94 1.69 140 684.74 1.69 

141 689.89 1.72 141 689.79 1.73 

142 694.89 1.69 

143 699.94 1.51 143 699.89 1.64 

144 704.92 1.48 

145 709.89 1.44 145 709.79 1.47 

146 714.84 1.68 146 714.74 1.76 

147 719.69 1.69 147 719.79 1.75 

148 724.74 1.77 148 724.79 1.77 

149 729.78 1.71 149 729.83 1.76 

150 734.78 1.83 

151 739.71 1.9 151 739.68 1.94 

152 744.66 1.91 152 744.64 1.94 

153 749.74 1.93 153 749.73 1.96 

154 754.64 1.96 154 754.64 1.98 

155 759.68 1.96 155 759.68 1.98 

156 764.67 1.93 156 764.68 1.95 

157 769.77 1.9 157 769.79 1.91 

158 775.16 1.9 158 775.19 1.91 

159 779.6 2.04 159 779.64 2.04 

160 784.68 1.88 160 784.73 1.88 

161 789.64 1.89 161 789.69 1.89 

162 794.78 1.86 

163 799.78 1.85 163 799.84 1.86 

164 804.73 1.89 164 804.79 1.9 

165 809.58 1.92 165 809.64 1.93 

166 814.77 1.9 166 814.84 1.92 

167 819.62 1.94 167 819.69 1.96 

168 824.62 2.01 168 824.69 2.03 

169 829.5 2.08 169 829.58 2.1 

170 834.61 2 170 834.69 2.02 

171 839.65 1.92 171 839.73 1.95 

172 844.6 1.95 172 844.69 1.98 
31

173 849.64 1.97 173 849.73 2 

174 854.45 1.94 174 854.54 1.97 

175 859.49 2 175 859.58 2.04 

176 864.43 2.11 176 864.53 2.15 

177 869.43 2.14 177 869.53 2.18 

178 874.49 2.03 178 874.59 2.08 

179 879.53 1.97 179 879.64 2.02 

180 884.53 2.01 180 884.64 2.06 

181 889.57 1.97 181 889.68 2.03 

182 894.43 2.05 182 894.54 2.11 

183 899.62 2 183 899.74 2.07 

184 904.57 2.08 184 904.69 2.15 

185 909.47 2.08 185 909.59 2.16 

186 914.42 2.06 186 914.54 2.15 

187 919.57 2.07 187 919.69 2.16 

188 924.46 2.11 188 924.59 2.21 

189 929.46 2.17 189 929.59 2.27 

190 934.46 2.14 190 934.59 2.25 

191 939.46 2.13 191 939.59 2.25 

192 944.46 2.07 192 944.59 2.19 

193 949.34 2.15 193 949.48 2.28 

194 954.49 2.19 194 954.63 2.32 

195 959.45 2.22 195 959.59 2.36 

196 964.2 2.28 196 964.34 2.43 

197 969.4 2.22 197 969.54 2.37 

198 974.14 2.11 198 974.29 2.27 

199 979.24 2.13 199 979.39 2.29 

200 984.49 2.23 200 984.64 2.4 

201 989.46 2.3 201 989.59 2.47 

202 994.57 2.23 202 994.69 2.39 

203 999.49 2.2 203 999.59 2.36 

204 1004.51 2.2 204 1004.59 2.36 

205 1009.38 2.27 205 1009.44 2.42 

206 1014.39 2.38 206 1014.44 2.53 

207 1019.35 2.4 207 1019.38 2.55 

208 1024.53 2.4 208 1024.54 2.54 

209 1029.54 2.34 209 1029.54 2.48 

210 1034.46 2.35 210 1034.44 2.48 

211 1039.27 2.26 211 1039.23 2.39 

212 1044.59 2.41 212 1044.54 2.54 

213 1049.61 2.53 213 1049.54 2.65 

214 1054.63 2.48 214 1054.54 2.6 

215 1059.59 2.54 215 1059.49 2.66 

216 1064.41 2.56 216 1064.29 2.67 

217 1069.73 2.59 217 1069.59 2.7 

218 1074.65 2.57 218 1074.49 2.68 

219 1079.71 2.66 219 1079.54 2.76 

220 1084.48 2.73 220 1084.29 2.83 

221 1089.68 2.76 221 1089.53 2.82 

222 1094.49 2.52 222 1094.38 2.53 

223 1099.56 2.57 223 1099.49 2.54 

224 1104.46 2.67 224 1104.44 2.6 

225 1109.57 2.72 225 1109.59 2.61 

226 1114.23 2.72 226 1114.29 2.56 

227 1119.29 2.83 227 1119.39 2.63 

228 1124.19 3.17 228 1124.34 2.91 

229 1129.14 3.32 

230 1134.19 3.46 

231 1139.04 3.07 

232 1144.24 3.17 

233 1149.19 3.07 

234 1150.33 4.66 234 1150.38 4.67 

235 1155.38 4.88 235 1155.54 4.73 

236 1160.23 4.53 236 1160.49 4.67 

237 1165.18 4.25 237 1165.43 4.5 

238 1170.18 4.15 238 1170.29 4.23 

239 1175.13 4.05 239 1175.23 4.11 

240 1180.13 3.95 240 1180.18 4.05 

241 1185.03 3.9 241 1185.08 3.96 

242 1190.03 3.95 242 1190.08 4.01 
32

243 1195.12 3.96 243 1195.18 4.02 

244 1200.02 4.18 244 1200.08 4.24 

245 1204.96 4.4 245 1205.03 4.46 

246 1209.96 4.26 246 1210.03 4.33 

247 1214.7 4.07 247 1214.78 4.14 

248 1219.85 3.98 248 1219.93 4.05 

249 1224.59 4.04 249 1224.68 4.11 

250 1229.64 4.11 250 1229.73 4.18 

251 1234.68 4.1 251 1234.77 4.17 

252 1239.57 4.1 252 1239.67 4.17 

253 1244.47 4.08 253 1244.57 4.15 

254 1249.56 4.07 254 1249.67 4.14 

255 1254.46 4.11 255 1254.57 4.18 

256 1259.26 4.03 256 1259.38 4.11 

257 1264.41 3.94 257 1264.53 4.02 

258 1269.3 3.97 258 1269.43 4.05 

259 1274.19 3.96 259 1274.32 4.04 

260 1279.18 4.02 260 1279.32 4.1 

261 1284.13 3.95 261 1284.27 4.03 

262 1289.15 4.04 262 1289.28 4.13 

263 1293.89 4.05 263 1294.02 4.14 

264 1299 4.03 264 1299.12 4.13 

265 1303.85 3.99 265 1303.97 4.1 

266 1308.91 3.98 266 1309.02 4.09 

267 1313.81 4.04 267 1313.92 4.16 

268 1318.82 4.06 268 1318.92 4.19 

269 1323.81 3.89 269 1323.91 4.03 

270 1328.68 3.89 270 1328.77 4.03 

271 1333.74 3.85 271 1333.82 4 

272 1338.64 4.02 272 1338.72 4.18 

273 1343.65 3.98 273 1343.72 4.14 

274 1348.75 4.03 274 1348.82 4.2 

275 1353.51 4.04 275 1353.57 4.22 

276 1358.61 4.17 276 1358.67 4.35 

277 1363.36 4.08 277 1363.41 4.27 

278 1368.31 4.1 278 1368.36 4.29 

279 1373.26 4.12 279 1373.46 4.35 

280 1378.37 4.23 280 1378.42 4.4 

281 1383.31 4.23 281 1383.36 4.46 

282 1388.26 4.24 282 1388.51 4.42 

283 1392.97 4.29 283 1393.21 4.47 

284 1398.08 4.3 284 1398.31 4.49 

285 1403.09 4.38 285 1403.31 4.57 

286 1408.05 4.37 286 1408.26 4.56 

287 1412.96 4.33 287 1413.16 4.53 

288 1417.97 4.27 288 1418.16 4.47 

289 1422.78 4.3 289 1422.96 4.51 

290 1427.89 3.41 290 1428.06 3.62 

291 1432.75 4.39 291 1432.91 4.6 

292 1437.82 4.35 292 1437.96 4.57 

293 1442.73 4.35 293 1442.86 4.57 

294 1447.74 4.37 294 1447.86 4.59 

295 1452.6 4.3 295 1452.71 4.53 

296 1457.61 4.29 296 1457.71 4.52 

297 1462.67 4.31 297 1462.76 4.55 

298 1467.63 4.39 298 1467.71 4.63 

299 1472.54 4.44 299 1472.61 4.68 

300 1477.54 4.38 300 1477.6 4.63 

301 1482.6 4.51 301 1482.65 4.76 

302 1487.51 4.73 302 1487.61 4.84 

303 1492.41 5.12 303 1492.56 5.08 

304 1497.3 5.4 304 1497.5 5.22 

305 1502.2 5.07 305 1502.5 5.38 

306 1507.1 4.58 306 1507.4 4.89 

307 1511.91 4.65 307 1512.2 4.96 

308 1516.86 4.63 308 1517.15 4.94 

309 1521.92 4.69 309 1522.21 5 

310 1526.92 4.62 310 1527.2 4.93 

311 1531.92 4.63 311 1532.2 4.94 

312 1536.77 4.72 312 1537.05 5.03 
33

313 1541.82 4.57 313 1542.1 4.87 

314 1546.73 4.53 314 1547 4.83 

315 1551.68 4.59 315 1551.95 4.89 

316 1556.57 4.63 316 1556.84 4.93 

317 1561.68 4.59 317 1561.94 4.89 

318 1566.53 4.6 318 1566.79 4.9 

319 1571.54 4.61 319 1571.8 4.91 

320 1576.5 4.53 320 1576.75 4.83 

321 1581.4 4.57 321 1581.65 4.87 

322 1586.31 4.56 322 1586.55 4.86 

323 1591.27 4.59 323 1591.5 4.89 

324 1596.07 4.6 324 1596.29 4.9 

325 1601.14 4.61 325 1601.35 4.91 

326 1606.14 4.59 326 1606.34 4.89 

327 1610.95 4.59 327 1611.14 4.89 

328 1616.01 4.62 328 1616.19 4.92 

329 1620.98 4.67 329 1621.15 4.97 

330 1626.09 4.63 330 1626.25 4.93 

331 1630.89 4.58 331 1631.04 4.88 

332 1635.8 4.61 332 1635.94 4.91 

333 1640.86 4.59 333 1640.99 4.89 

334 1645.77 4.68 334 1645.89 4.98 

335 1650.87 4.66 335 1650.98 4.96 

336 1655.69 4.64 336 1655.79 4.94 

337 1660.7 4.73 337 1660.79 5.03 

338 1665.5 4.77 338 1665.58 5.07 

339 1670.52 4.76 339 1670.59 5.06 

340 1675.58 4.72 340 1675.64 5.02 

341 1680.49 4.72 341 1680.54 5.02 

342 1685.43 4.68 342 1685.49 4.98 

343 1690.4 4.74 343 1690.48 5.05 

344 1695.24 4.83 344 1695.33 5.14 

345 1700.08 4.67 345 1700.18 4.99 

346 1705.23 4.69 346 1705.34 5.01 

347 1710.01 4.72 347 1710.13 5.05 

348 1714.89 4.77 348 1715.03 5.1 

349 1719.93 4.69 349 1720.08 5.03 

350 1724.87 4.76 350 1725.03 5.1 

351 1730.01 4.77 351 1730.18 5.11 

352 1734.79 4.78 352 1734.98 5.13 

353 1739.63 4.56 353 1739.83 4.91 

354 1744.77 4.74 354 1744.98 5.1 

355 1749.7 4.72 355 1749.93 5.08 

356 1754.64 4.89 356 1754.88 5.26 

357 1759.43 4.86 357 1759.68 5.23 

358 1764.37 4.83 358 1764.63 5.21 

359 1769.3 4.93 359 1769.58 5.31 

360 1774.39 4.98 360 1774.68 5.37 

361 1779.33 5.03 361 1779.63 5.42 

362 1784.17 5.24 362 1784.48 5.63 

363 1789.2 5.35 363 1789.52 5.74 

364 1794.14 5.33 

365 1799.09 5.24 365 1799.43 5.63 

366 1804.18 5.13 366 1804.53 5.52 

367 1808.96 5.1 367 1809.32 5.49 

368 1813.86 5.06 368 1814.23 5.45 

369 1818.84 5.07 369 1819.22 5.46 

370 1823.83 4.95 370 1824.22 5.34 

371 1828.77 4.99 371 1829.17 5.38 

372 1833.75 4.9 372 1834.17 5.3 

373 1838.49 4.96 373 1838.92 5.36 

374 1843.23 4.98 374 1843.67 5.38 

375 1848.22 4.99 375 1848.67 5.39 

376 1853.11 4.95 376 1853.57 5.35 

377 1858.1 4.96 377 1858.57 5.36 

378 1863.24 5.09 378 1863.72 5.49 

379 1868.13 5.09 379 1868.62 5.49 

380 1873.12 5.15 380 1873.62 5.55 

381 1878.06 5.14 381 1878.57 5.54 

382 1883.09 5.09 382 1883.57 5.49 
34

383 1888 5.13 383 1888.46 5.53 

384 1892.98 5.08 384 1893.41 5.48 

385 1898.02 5.04 385 1898.42 5.44 

386 1903.13 5.06 386 1903.51 5.47 

387 1907.96 4.97 387 1908.31 5.38 

388 1913.05 5.03 388 1913.37 5.44 

389 1917.96 5.02 389 1918.26 5.43 

390 1922.84 5.08 390 1923.11 5.49 

391 1927.53 5.16 

392 1933.11 5.25 392 1933.32 5.66 

393 1937.93 5.22 393 1938.12 5.63 

394 1943.01 5.19 394 1943.17 5.6 

395 1947.98 5.36 395 1948.11 5.77 

396 1953.11 5.2 396 1953.22 5.62 

397 1958.18 5.14 397 1958.26 5.56 

398 1963.31 5.13 398 1963.36 5.55 

399 1968.28 5.16 399 1968.31 5.58 

400 1973.16 5.25 400 1973.16 5.67 

401 1978.15 5.21 401 1978.16 5.62 

402 1983.1 5.11 402 1983.12 5.52 

403 1988.09 5.11 403 1988.11 5.51 

404 1993.08 5.17 404 1993.11 5.56 

405 1998.02 5.16 405 1998.06 5.54 

406 2003.07 5.14 406 2003.11 5.51 

407 2008.06 5.11 407 2008.11 5.48 

408 2013.16 5.12 408 2013.22 5.48 

409 2018.14 5.1 409 2018.21 5.45 

410 2023.14 5.22 410 2023.21 5.56 

411 2028.18 5.18 411 2028.26 5.52 

412 2033.12 5.2 412 2033.21 5.53 

413 2038.11 5.27 413 2038.21 5.59 

414 2042.96 5.26 414 2043.06 5.57 

415 2048 5.16 415 2048.11 5.47 

416 2053.24 5.14 

417 2058.23 5.15 417 2058.36 5.44 

418 2063.32 5.25 418 2063.46 5.53 

419 2068.27 5.21 419 2068.41 5.49 

420 2073.26 5.23 420 2073.41 5.5 

421 2078.31 5.19 421 2078.46 5.46 

422 2083.2 5.2 422 2083.36 5.48 

423 2088.24 5.24 423 2088.41 5.52 

424 2093.39 5.17 424 2093.56 5.46 

425 2098.14 5.16 425 2098.31 5.45 

426 2103.19 5.17 426 2103.37 5.46 

427 2108.23 5.2 427 2108.41 5.5 

428 2113.12 5.23 428 2113.31 5.53 

429 2118.06 5.3 

430 2123.11 5.13 430 2123.31 5.44 

431 2128.21 5.14 431 2128.41 5.45 

432 2133.15 5.12 432 2133.36 5.44 

433 2138.25 5.14 433 2138.46 5.46 

434 2142.94 5.31 434 2143.16 5.64 

435 2148.04 5.4 435 2148.26 5.73 

436 2153.18 5.18 436 2153.41 5.51 

437 2157.98 5.38 437 2158.21 5.72 

438 2162.97 5.42 438 2163.21 5.76 

439 2168.02 5.44 439 2168.27 5.79 

440 2173.01 5.49 440 2173.26 5.84 

441 2177.92 5.51 441 2178.11 5.87 

442 2182.88 5.48 442 2183.01 5.84 

443 2187.59 5.64 443 2187.67 6.01 

444 2192.65 5.62 444 2192.67 5.99 

445 2197.45 5.62 445 2197.41 6 

446 2202.67 5.64 446 2202.57 6.02 

447 2207.12 5.66 447 2206.97 6.05 

448 2211.98 5.65 448 2211.77 6.04 

449 2216.49 5.74 449 2216.22 6.14 

450 2221.09 5.8 450 2220.77 6.21 

451 2225.65 5.73 451 2225.27 6.14 

452 2229.96 5.72 452 2229.52 6.14 
35

453 2234.77 5.72 453 2234.27 6.14 

454 2238.64 5.68 454 2238.08 6.11 

455 2242.74 5.61 455 2242.13 6.04 

456 2246.61 5.84 456 2245.94 6.28 

457 2250.57 5.55 

458 2254.51 5.8 458 2253.73 6.25 

459 2258.18 5.81 459 2257.34 6.26 

460 2261.99 5.71 460 2261.09 6.17 

461 2266.07 5.57 461 2265.19 6.01 

462 2269.76 5.56 462 2268.9 5.98 

463 2273.35 5.5 463 2272.5 5.91 

464 2276.78 5.56 464 2275.95 5.95 

465 2280.56 5.35 465 2279.75 5.72 

466 2284 5.46 466 2283.21 5.81 

467 2287.74 5.25 467 2286.96 5.58 

468 2291.57 5.3 468 2290.81 5.62 

469 2295.36 5.37 

470 2298.94 5.62 470 2298.21 5.9 

471 2302.83 5.63 471 2302.12 5.89 

472 2306.76 5.7 472 2306.07 5.94 

473 2310.84 5.7 473 2310.17 5.93 

474 2314.98 5.72 

475 2319.26 5.79 

476 2323.74 5.68 476 2323.12 5.85 

477 2328.13 5.79 477 2327.53 5.94 

478 2332.81 5.86 478 2332.23 6 

479 2337.3 5.89 479 2336.73 6.01 

480 2341.78 5.98 480 2341.23 6.08 

481 2346.61 5.95 481 2346.08 6.05 

482 2351.4 5.97 482 2350.89 6.06 

483 2356.12 5.99 483 2355.63 6.08 

484 2361.01 5.99 484 2360.54 6.08 

485 2366.23 6.04 485 2365.78 6.13 

486 2370.92 6.14 486 2370.49 6.23 

487 2376.09 6.28 487 2375.68 6.36 

488 2381.13 6.2 488 2380.74 6.28 

489 2386.16 6.29 489 2385.79 6.37 

490 2391.29 6.24 490 2390.94 6.31 

491 2396.03 6.26 491 2395.69 6.33 

492 2401.01 6.4 492 2400.69 6.47 

493 2405.94 6.49 

494 2411.12 6.53 

495 2415.95 6.55 495 2415.69 6.61 

496 2420.98 6.58 

497 2425.81 6.58 497 2425.59 6.64 

498 2430.84 6.55 498 2430.64 6.6 

499 2435.97 6.54 499 2435.79 6.59 

500 2440.79 6.57 500 2440.63 6.62 

501 2445.78 6.61 501 2445.64 6.65 

502 2450.77 6.71 502 2450.64 6.75 

503 2455.65 6.66 503 2455.54 6.69 

504 2460.79 6.6 504 2460.69 6.63 

505 2465.77 6.5 505 2465.69 6.52 

506 2470.61 6.47 

507 2475.74 6.39 507 2475.69 6.4 

508 2480.63 6.19 508 2480.59 6.19 

509 2485.61 6.06 509 2485.59 6.06 

510 2490.65 5.92 510 2490.64 5.91 

511 2495.58 5.82 511 2495.59 5.8 

512 2500.56 5.77 512 2500.59 5.75 

513 2505.5 5.8 513 2505.54 5.77 

514 2510.58 5.83 

515 2515.62 5.9 515 2515.69 5.86 

516 2520.6 5.93 516 2520.69 5.88 

517 2525.49 5.91 517 2525.59 5.86 

518 2530.43 6.03 518 2530.55 5.97 

519 2535.46 6.04 519 2535.59 5.98 

520 2540.44 6.05 520 2540.59 5.98 

521 2545.21 6.06 521 2545.34 6 

522 2550.33 6.08 522 2550.44 6.03 
36

523 2555.27 6.06 523 2555.35 6.02 

524 2560.38 6.15 524 2560.44 6.12 

525 2565.45 6.39 525 2565.49 6.37 

526 2569.72 6.67 526 2569.74 6.66 

527 2574.55 6.94 527 2574.54 6.94 

528 2579.13 7.02 528 2579.1 7.03 

529 2584.05 7.06 529 2584 7.08 

530 2588.72 7.07 530 2588.65 7.1 

531 2593.65 7.08 531 2593.55 7.12 

532 2598.17 7.12 532 2598.05 7.17 

533 2602.89 7.1 533 2602.75 7.16 

534 2607.73 7.05 534 2607.56 7.12 

535 2612.29 7.14 535 2612.1 7.22 

536 2617.07 7.16 536 2616.86 7.25 

537 2621.69 7.14 537 2621.46 7.24 

538 2626.26 7.19 538 2626 7.3 

539 2630.54 7.05 539 2630.26 7.17 

540 2635.76 7.17 540 2635.46 7.3 

541 2640.3 7.14 541 2640.01 7.27 

542 2645.09 7.22 

543 2649.77 7.16 543 2649.51 7.29 

544 2654.61 7.16 544 2654.36 7.29 

545 2659.15 7.22 545 2658.91 7.34 

546 2663.85 7.18 546 2663.62 7.3 

547 2668.68 7.22 547 2668.47 7.34 

548 2673.17 7.19 548 2672.97 7.31 

549 2677.96 7.22 549 2677.77 7.34 

550 2682.59 7.24 550 2682.42 7.36 

551 2687.18 7.24 551 2687.02 7.36 

552 2691.88 7.28 552 2691.73 7.4 

553 2696.67 7.29 553 2696.53 7.41 

554 2701.41 7.36 554 2701.28 7.48 

555 2705.99 7.38 555 2705.88 7.5 

556 2710.73 7.41 556 2710.63 7.52 

557 2715.52 7.44 557 2715.43 7.55 

558 2720.66 7.46 558 2720.58 7.57 

559 2725.39 7.47 559 2725.33 7.58 

560 2730.43 7.45 560 2730.38 7.56 

561 2735.41 7.47 561 2735.38 7.55 

562 2740.34 7.47 562 2740.33 7.51 

563 2745.43 7.47 563 2745.44 7.48 

564 2750.36 7.52 564 2750.38 7.5 

565 2755.29 7.56 565 2755.33 7.5 

566 2760.32 7.55 566 2760.38 7.46 

567 2765.25 7.45 567 2765.33 7.33 

568 2769.98 7.45 568 2770.08 7.29 

569 2774.91 7.44 569 2775.03 7.25 

570 2779.74 7.53 570 2779.87 7.31 

571 2784.63 7.58 571 2784.78 7.33 

572 2789.41 7.74 572 2789.58 7.45 

573 2794.19 7.81 573 2794.38 7.49 

574 2799.12 7.95 574 2799.33 7.6 

575 2803.94 7.98 575 2804.17 7.59 

576 2808.73 8.04 576 2808.97 7.62 

577 2813.61 8.16 577 2813.87 7.71 

578 2818.49 8 

579 2823.32 7.64 579 2823.62 7.12 

580 2828.32 7.41 580 2828.42 7.07 

581 2833.17 7.66 581 2833.12 7.18 

Appendix C 

Distances and elevations along East Bay Seismic Profile 2 (SL-2). 

Measurements are relative to the first receiver point at the west end of Profile SL-2. 

Station No. Receiver Dist. (m) Receiver Elev. 

(m) 

Station No. Shot Dist. (m) Shot Elev. (m) 

1 0 2.15 1 0 2.15 

2 5.05 1.63 2 5.05 1.63 
37

3 9.83 1.2 3 9.83 1.2 

4 14.6 0.75 4 14.6 0.75 

5 19.23 0.44 5 19.23 0.44 

6 24.05 0.34 6 24.05 0.34 

7 28.63 0.32 7 28.63 0.32 

8 33.51 0.29 8 33.51 0.29 

9 38.11 0.27 9 38.11 0.27 

10 42.57 0.22 10 42.57 0.22 

11 47.04 0.16 11 47.04 0.16 

12 51.55 0.18 12 51.55 0.18 

13 55.96 0.13 13 55.96 0.13 

14 60.49 0.11 

15 65 0.18 15 65 0.18 

16 69.47 0.17 16 69.47 0.17 

17 73.92 0.17 17 73.92 0.17 

18 78.33 0.17 18 78.33 0.17 

19 82.86 0.18 19 82.86 0.18 

20 87.39 0.19 20 87.39 0.19 

21 91.92 0.2 21 91.92 0.2 

22 96.45 0.2 22 96.45 0.2 

23 100.86 0.19 23 100.86 0.19 

24 105.3 0.18 24 105.3 0.18 

25 109.76 0.15 25 109.76 0.15 

26 114.22 0.14 26 114.22 0.14 

27 118.88 0.12 27 118.88 0.12 

28 123.55 0.08 28 123.55 0.08 

29 128.71 0.13 29 128.71 0.13 

30 133.35 0.14 30 133.35 0.14 

31 138.36 0.18 31 138.36 0.18 

32 143.24 0.29 32 143.24 0.29 

33 148.14 0.26 33 148.14 0.26 

34 153.17 0.4 34 153.17 0.4 

35 158.28 0.46 35 158.28 0.46 

36 163.18 0.46 

37 168.26 0.47 37 168.26 0.47 

38 173.29 0.55 38 173.29 0.55 

39 178.28 0.49 39 178.28 0.49 

40 183.23 0.53 40 183.23 0.53 

41 188.17 0.6 41 188.17 0.6 

42 193.31 0.65 42 193.31 0.65 

43 198.2 0.69 43 198.2 0.69 

44 203.22 0.57 44 203.22 0.57 

45 208.37 0.6 45 208.37 0.6 

46 213.13 0.65 46 213.13 0.65 

47 218.22 0.69 47 218.22 0.69 

48 223.16 0.66 48 223.16 0.66 

49 228.23 0.72 49 228.23 0.72 

50 233.25 0.76 50 233.25 0.76 

51 238.13 0.8 

52 243.15 0.7 52 243.15 0.7 

53 248.03 0.8 53 248.03 0.8 

54 253.04 0.87 54 253.04 0.87 

55 258.04 0.85 55 258.04 0.85 

56 263.11 0.75 56 263.11 0.75 

57 268.02 0.93 57 268.02 0.93 

58 272.99 0.82 58 272.99 0.82 

59 277.98 0.92 59 277.98 0.92 

60 283.27 1.03 60 283.27 1.03 

61 288.09 1.03 61 288.09 1.03 

62 293.11 1.01 62 293.11 1.01 

63 298.08 1.02 63 298.08 1.02 

64 302.9 1.03 64 302.9 1.03 

65 307.56 1.02 65 307.56 1.02 

66 312.39 0.76 66 312.39 0.76 

67 317.54 0.74 67 317.54 0.74 

68 322.37 0.91 68 322.37 0.91 

69 327.34 0.94 69 327.34 0.94 

70 332.19 0.96 70 332.19 0.96 

71 337.05 0.94 71 337.05 0.94 

72 342.27 0.97 72 342.27 0.97 
38

73 347.28 0.91 73 347.28 0.91 

74 352.31 0.9 74 352.31 0.9 

75 357.27 0.92 75 357.27 0.92 

76 362.16 0.86 76 362.16 0.86 

77 367.07 0.83 77 367.07 0.83 

78 372.13 0.78 78 372.13 0.78 

79 377.12 0.74 79 377.12 0.74 

80 382.12 0.77 80 382.12 0.77 

81 387.06 0.8 81 387.06 0.8 

82 391.98 0.77 82 391.98 0.77 

83 396.61 0.64 83 396.61 0.64 

84 401.26 1.06 84 401.26 1.06 

85 405.72 1.07 85 405.72 1.07 

86 409.81 1.11 86 409.81 1.11 

87 414.04 1.03 87 414.04 1.03 

88 417.98 1.19 88 417.98 1.19 

89 422 1.18 89 422 1.18 

90 426.29 1.21 90 426.29 1.21 

91 429.87 1.22 91 429.87 1.22 

92 434.1 1.24 92 434.1 1.24 

93 438.4 1.63 93 438.4 1.63 

94 442.56 1.67 94 442.56 1.67 

95 446.86 1.79 95 446.86 1.79 

96 451.15 1.84 96 451.15 1.84 

97 455.59 1.87 97 455.59 1.87 

98 460.1 1.82 98 460.1 1.82 

99 464.68 1.93 99 464.68 1.93 

100 469.57 1.88 100 469.57 1.88 

101 474.5 1.91 101 474.5 1.91 

102 479.4 1.93 102 479.4 1.93 

103 484.34 1.92 103 484.34 1.92 

104 489.22 1.86 104 489.22 1.86 

105 494.28 1.85 105 494.28 1.85 

106 499.22 1.79 106 499.22 1.79 

107 504.16 1.83 107 504.16 1.83 

108 509.23 1.75 108 509.23 1.75 

109 514.21 1.8 109 514.21 1.8 

110 519.04 1.9 110 519.04 1.9 

111 524.03 1.87 111 524.03 1.87 

112 529.02 1.87 112 529.02 1.87 

113 533.91 1.91 113 533.91 1.91 

114 538.96 1.89 114 538.96 1.89 

115 543.81 1.9 115 543.81 1.9 

116 548.68 1.84 116 548.68 1.84 

117 553.8 1.89 117 553.8 1.89 

118 558.67 1.89 118 558.67 1.89 

119 563.72 1.99 119 563.72 1.99 

120 568.57 2.02 

121 573.51 2 121 573.51 2 

122 578.68 2 122 578.68 2 

123 583.61 2.19 123 583.61 2.19 

124 588.62 2.2 124 588.62 2.2 

125 593.47 2.28 125 593.47 2.28 

126 598.64 2.33 126 598.64 2.33 

127 603.52 2.34 127 603.52 2.34 

128 608.67 2.5 128 608.67 2.5 

129 613.6 2.56 129 613.6 2.56 

130 618.56 2.55 130 618.56 2.55 

131 623.46 2.47 131 623.46 2.47 

132 628.24 2.46 132 628.24 2.46 

133 632.94 2.54 133 632.94 2.54 

134 637.57 2.44 134 637.57 2.44 

135 642.1 2.51 135 642.1 2.51 

136 646.7 2.42 136 646.7 2.42 

137 651.19 2.43 137 651.19 2.43 

138 655.34 2.42 138 655.34 2.42 

139 659.49 2.43 139 659.49 2.43 

140 663.18 2.48 140 663.18 2.48 

141 666.74 2.42 141 666.74 2.42 

142 670.55 2.44 142 670.55 2.44 
39

143 673.48 2.56 143 673.48 2.56 

144 677.08 2.81 

145 680.76 3.47 145 680.76 3.47 

146 684.11 3.6 146 684.11 3.6 

147 687.5 3.7 147 687.5 3.7 

148 691.15 3.77 148 691.15 3.77 

149 694.31 3.81 149 694.31 3.81 

150 697.77 3.81 150 697.77 3.81 

151 701.18 3.81 151 701.18 3.81 

152 704.84 3.77 152 704.84 3.77 

153 708.34 3.85 153 708.34 3.85 

154 711.94 3.9 

155 715.36 3.86 

156 718.86 3.86 

157 722.36 3.86 

158 725.86 3.86 

159 729.36 3.86 

Appendix D 

Distances and elevations along East Bay Seismic Profile 3 (SL-3). 

Measurements are relative to the first shotpoint at the west end of Profile SL-3. 

Station No. Receiver Dist. (m) Receiver Elev. 

(m) 

Station No. Shot Dist. (m) Shot Elev. (m) 

1 0.22 0.04 1 0 0.41 

2 5.29 0.2 2 5.05 0.56 

3 10.09 0.24 3 9.84 0.59 

4 14.87 0.23 4 14.6 0.58 

5 19.82 0.23 5 19.54 0.57 

6 24.86 0.26 6 24.56 0.59 

7 29.79 0.12 

8 34.52 0.25 8 34.19 0.56 

9 39.65 0.15 9 39.31 0.45 

10 44.44 0.19 10 44.08 0.49 

11 49.4 0 

12 54.03 0.09 12 53.64 0.37 

13 58.84 0.22 13 58.44 0.49 

14 63.13 0.49 14 62.71 0.75 

15 67.45 0.49 15 67.02 0.75 

16 72.03 0.61 16 71.58 0.86 

17 76.74 0.6 17 76.28 0.84 

18 81.14 0.51 18 80.66 0.74 

19 85.77 0.44 19 85.28 0.66 

20 90.24 0.35 20 89.73 0.57 

21 94.63 0.43 21 94.11 0.64 

22 99.28 0.52 22 98.74 0.72 

23 103.68 0.65 23 103.13 0.84 

24 108.21 0.68 24 107.64 0.86 

25 112.61 1.11 25 112.03 1.28 

26 116.62 1.66 26 116.02 1.83 

27 121.08 2.16 27 120.47 2.32 

28 125.73 2.15 28 125.1 2.3 

29 130.29 1.71 29 130.2 1.99 

30 135.05 1.24 30 135.2 1.33 

31 140 1.02 31 140.17 1.15 

32 144.99 1.03 32 145.02 1.18 

33 149.96 1.03 33 149.8 1.2 

34 154.85 1.04 34 154.76 1.19 

35 159.85 1.02 35 159.88 1.11 

36 164.55 0.99 36 164.64 1.12 

37 169.66 1.03 

38 174.34 0.94 38 174.44 1.17 

39 178.88 0.96 39 179.27 1.03 

40 183.66 0.8 40 183.94 0.98 

41 188.16 0.89 41 188.49 0.97 

42 192.56 0.86 42 192.83 1.03 

43 197.1 0.79 43 197.37 0.95 

44 201.57 1 44 201.9 0.98 
40

45 205.96 1.24 45 206.25 1.24 

46 210.51 1 46 210.77 1.02 

47 215.09 1.04 47 215.31 1.08 

48 219.53 0.94 48 219.72 1 

49 223.99 0.88 49 224.14 0.96 

50 228.68 0.69 50 228.8 0.79 

51 233.22 0.54 51 233.3 0.66 

52 238.04 0.75 52 238.09 0.89 

53 242.9 0.47 53 242.91 0.63 

54 247.98 0.52 54 247.96 0.7 

55 252.85 0.54 55 252.8 0.74 

56 257.79 0.53 56 257.7 0.75 

57 263.07 0.61 57 262.74 0.79 

58 267.89 0.6 58 267.56 0.79 

59 272.85 0.79 59 272.56 0.83 

60 277.68 0.88 60 277.28 0.88 

61 282.54 0.82 61 281.96 0.9 

62 286.84 1.08 62 286.21 0.93 

63 291.56 0.9 63 290.97 1.1 

64 296.01 0.97 64 295.37 1.27 

65 300.35 1.03 65 299.64 1.39 

66 304.71 1.04 66 304.03 1.36 

67 308.8 1.03 67 308.14 1.32 

68 312.87 1.12 68 312.24 1.37 

69 317.2 1.34 69 316.6 1.55 

70 321.43 1.31 70 320.86 1.48 

71 325.63 1.45 71 325.08 1.59 

72 329.83 1.5 72 329.31 1.6 

73 334.23 1.59 73 333.53 1.66 

74 338.5 1.66 74 337.86 1.84 

75 343.01 1.71 75 342.48 1.88 

76 347.57 1.71 76 347.17 1.82 

77 352.3 1.75 77 352.03 1.85 

78 357.09 1.76 78 356.76 1.87 

79 361.86 1.78 79 361.65 1.83 

80 366.71 1.82 80 366.53 1.92 

81 371.8 1.82 81 371.64 1.96 

82 376.66 1.84 82 376.64 1.98 

83 381.58 1.84 83 381.56 1.95 

84 386.48 1.77 

85 391.43 1.82 

86 396.32 1.83 86 396.34 1.92 

87 400.92 2.04 

88 405.54 2.13 88 405.76 2.23 

89 409.76 1.76 89 410 1.87 

90 414.28 1.59 

91 419.32 1.61 91 419.58 1.74 

92 423.59 1.6 

93 428.17 1.56 93 428.46 1.71 

94 433.07 1.56 

95 437.6 1.49 

96 442.05 1.54 96 442.38 1.72 

97 446.33 1.59 97 446.67 1.78 

98 450.93 1.6 98 451.39 1.72 

99 455.53 1.56 

100 460.07 1.51 100 460.53 1.68 

101 464.55 1.49 101 465 1.61 

102 469.27 1.46 102 469.61 1.58 

103 474.25 1.42 103 474.59 1.62 

104 478.99 1.41 104 479.21 1.61 

105 484 1.49 105 483.96 1.58 

106 488.97 1.47 106 488.91 1.57 

107 493.99 1.67 107 493.92 1.78 

108 499.05 1.66 108 498.96 1.78 

109 504.08 1.72 109 503.98 1.85 

110 509.12 1.83 110 509 1.97 

111 514.04 1.81 111 513.9 1.96 

112 519.33 1.79 112 519.18 1.95 

113 524.19 1.88 113 524.02 2.05 

114 529.17 1.94 114 528.99 2.12 
41

115 534.95 2.02 115 534.75 2.21 

116 538.7 2.06 116 538.92 2.14 

117 543.78 2.15 117 543.46 2.21 

118 548.12 2.19 118 548.4 2.31 

119 553.42 2.14 

120 558.36 2.13 

121 562.8 2.06 

122 567.65 2.06 122 567.94 2.21 

123 572.63 2.03 123 572.87 2.18 

124 577.3 2.05 124 577.49 2.19 

125 582.34 2.04 125 582.48 2.18 

126 587.01 2.05 126 587.1 2.19 

127 591.5 2.25 127 591.54 2.39 

128 596.12 2.34 128 596.52 2.59 

129 600.92 2.38 129 601.08 2.57 

130 605.84 2.37 130 606.19 2.59 

131 610.59 2.48 131 610.93 2.46 

132 615.22 2.36 132 615.56 2.35 

133 620.19 2.3 133 620.53 2.3 

134 625.06 2.31 134 625.4 2.33 

135 629.63 2.24 135 629.96 2.27 

136 634.38 2.24 136 634.71 2.28 

137 639.24 2.2 137 639.57 2.25 

138 643.85 2.16 138 644.18 2.23 

139 648.96 2.24 139 649.29 2.32 

140 653.75 2.31 140 654.09 2.3 

141 658.15 2.29 141 658.46 2.28 

142 663.35 2.43 142 663.63 2.42 

143 667.95 2.46 143 668.19 2.46 

144 672.73 2.41 144 672.94 2.41 

Appendix E 

Distances and elevations along East Bay Seismic Profile 4 (SL-4). 

Measurements are relative to the first receiver point at the west end of Profile SL-4. 

Station No. Receiver Dist. (m) Receiver Elev. 

(m) 

Station No. Shot Dist. (m) Shot Elev. (m) 

1 0 0.99 

2 5.07 1.39 2 5.21 1.22 

3 10.56 1.2 3 10.27 1.22 

4 15.21 1.12 4 14.91 1.15 

5 20.16 1.12 

6 25.15 1.19 

7 30.1 1.08 

8 35.13 1.07 

9 40.17 1.17 

10 44.99 1.29 

11 50.02 1.3 

12 55.16 1.38 

13 60.02 1.47 

14 65.06 1.52 

15 70.19 1.56 

16 75.01 1.59 

17 80 1.52 

18 85.09 1.51 

19 90.08 1.49 

20 95.12 1.4 

21 99.94 1.31 

22 104.98 1.2 

23 110.06 1.19 

24 115.11 1.03 

25 120.01 1.1 

26 125.63 1.14 

27 130.09 1.15 

28 135.13 1.17 

29 140 1.07 

30 145.04 0.98 

31 149.94 0.82 
42

32 154.98 0.7 32 155 0.63 

33 160.07 0.73 33 160.22 0.69 

34 164.44 0.76 34 164.46 0.7 

35 169.84 0.72 35 170.21 0.7 

36 174.92 0.77 36 174.94 0.71 

37 179.91 0.72 37 179.97 0.7 

38 184.95 0.71 38 184.97 0.67 

39 190.25 0.69 39 190.1 0.7 

40 194.94 0.68 40 195.05 0.66 

41 199.93 0.68 41 199.83 0.67 

42 204.88 0.65 42 204.86 0.63 

43 209.93 0.63 43 210.04 0.62 

44 214.92 0.56 44 214.9 0.51 

45 219.95 0.57 45 219.71 0.54 

46 224.82 0.55 46 225.15 0.58 

47 230.26 0.55 47 230.2 0.56 

48 234.9 0.57 48 235.02 0.56 

49 239.89 0.55 49 240.09 0.55 

50 244.89 0.56 50 244.96 0.55 

51 249.88 0.64 51 249.96 0.62 

52 254.92 0.65 52 254.72 0.63 

53 259.92 0.56 53 259.85 0.52 

54 264.95 0.37 54 264.97 0.5 

55 269.91 0.48 

Appendix F 

Distances and elevations along East Bay Seismic Profile 5 (SL-5). 

Measurements are relative to the first receiver point at the west end of Profile SL-5. 

Station No. Receiver Dist. (m) Receiver Elev. 

(m) 

Station No. Shot Dist. (m) Shot Elev. (m) 

1 0.04 0.14 

2 5.05 0.15 

3 9.62 0.3 

4 14.71 0.53 

5 19.04 0.47 

6 24.46 0.44 

7 30.5 0.51 

8 35.04 0.46 

9 40 0.41 9 40.06 0.37 

10 44.93 0.37 10 44.86 0.34 

11 49.86 0.44 11 49.71 0.41 

12 54.87 0.56 12 54.77 0.56 

13 59.78 0.69 13 59.84 0.68 

14 64.89 0.77 14 64.74 0.76 

15 69.95 0.78 

16 74.91 0.79 16 74.87 0.82 

17 79.96 0.87 17 79.91 0.89 

18 84.98 0.83 18 84.92 0.85 

19 89.83 0.89 19 89.83 0.88 

20 94.83 0.96 

21 99.84 0.92 21 99.95 0.95 

22 104.9 1.04 22 104.96 1.05 

23 109.91 1.07 23 110.14 1.1 

24 114.87 1.14 24 114.83 1.1 

25 119.88 1.16 25 119.9 1.15 

26 124.9 1.17 26 124.9 1.15 

27 129.95 1.17 27 129.51 1.09 

28 135 1.21 28 134.93 1.18 

29 139.81 1.22 29 139.82 1.17 

30 144.86 1.28 30 144.83 1.26 

31 149.87 1.24 31 149.63 1.23 

32 154.67 1.23 

33 159.73 1.21 33 159.81 1.17 

34 164.74 1.18 34 164.61 1.14 

35 169.8 1.13 35 169.81 1.12 

36 174.76 1.1 36 174.84 1.03 

37 179.86 1.08 37 179.69 1.07 
43

38 184.83 0.99 38 184.79 0.96 

39 189.79 0.91 39 189.89 0.9 

40 194.87 0.91 40 194.77 0.88 

41 199.83 0.88 41 199.68 0.91 

42 204.79 0.86 42 204.8 0.9 

43 209.8 0.86 

44 214.72 0.83 44 214.68 0.88 

45 219.68 0.86 45 219.9 0.85 

46 224.85 0.89 46 224.81 0.88 

47 229.76 0.88 47 229.68 0.88 

48 234.73 0.89 48 234.6 0.86 

49 239.64 0.83 49 239.65 0.81 

50 244.86 0.77 

51 250.03 0.75 

52 254.8 0.69 

53 259.63 0.65 

54 264.63 0.65 54 264.74 0.64 

55 269.48 1.26 

56 274.56 0.87 

57 279.64 0.47 

58 284.38 0.46 58 284.44 0.43 

Appendix G 

Distances and elevations along East Bay Seismic Profile 6 (SL-6). 

Measurements are relative to the first receiver point at the west end of Profile SL-6. 

Station No. Receiver Dist. (m) Receiver Elev. 

(m) 

Station No. Shot Dist. (m) Shot Elev. (m) 

1 0 0.07 1 0 0.07 

2 5.64 0.17 2 5.64 0.17 

3 10.36 0 3 10.36 0 

4 15.4 0.05 4 15.4 0.05 

5 20.66 0.05 5 20.66 0.05 

6 25.52 0.16 6 25.52 0.16 

7 30.43 0.17 7 30.43 0.17 

8 35.47 0.19 8 35.47 0.19 

9 40.51 0.2 9 40.51 0.2 

10 45.46 0.25 10 45.46 0.25 

11 50.37 0.28 11 50.37 0.28 

12 55.54 0.26 12 55.54 0.26 

13 60.32 0.32 13 60.32 0.32 

14 65.4 0.29 14 65.4 0.29 

15 70.53 0.24 15 70.53 0.24 

16 75.48 0.07 16 75.48 0.07 

17 80.42 0.3 17 80.42 0.3 

18 85.45 0.24 18 85.45 0.24 

19 90.38 0.17 19 90.38 0.17 

20 95.42 0.13 20 95.42 0.13 

21 100.42 0.54 21 100.42 0.54 

22 105.24 0.16 22 105.24 0.16 

23 110.41 0.12 23 110.41 0.12 

24 115.36 0.26 24 115.36 0.26 

25 120.14 0.21 25 120.14 0.21 

26 125.57 0.24 26 125.57 0.24 

27 130.35 0.28 27 130.35 0.28 

28 134.94 0.29 28 134.94 0.29 

29 140.43 0.31 29 140.43 0.31 

30 145.33 0.48 30 145.33 0.48 

31 150.41 0.34 31 150.41 0.34 

32 155.28 0.37 32 155.28 0.37 

33 160.24 0.34 33 160.24 0.34 

34 165.32 0.4 34 165.32 0.4 

35 170.44 0.35 35 170.44 0.35 

36 175.42 0.36 36 175.42 0.36 

37 180.22 0.37 37 180.22 0.37 

38 185.26 0.42 38 185.26 0.42 

39 190.3 0.46 39 190.3 0.46 

40 195.2 0.47 40 195.2 0.47 
44

41 200.2 0.34 41 200.2 0.34 

42 205.11 0.1 42 205.11 0.1 

43 210.24 0.46 43 210.24 0.46 

44 215.32 0.47 44 215.32 0.47 

45 220.27 0.41 45 220.27 0.41 

46 225.05 0.11 46 225.05 0.11 

47 230.3 0.57 47 230.3 0.57 

48 235.21 0.57 48 235.21 0.57 

49 240.3 0.51 49 240.3 0.51 

50 245.25 0.55 50 245.25 0.55 

51 250.33 0.54 51 250.33 0.54 

52 255.23 0.54 52 255.23 0.54 

53 260.18 0.54 53 260.18 0.54 

54 265.27 0.51 54 265.27 0.51 

55 270.22 0.57 55 270.22 0.57 

56 275.31 0.6 56 275.31 0.6 

57 280.21 0.54 57 280.21 0.54 

58 285.34 0.59 58 285.34 0.59 

59 290.24 0.56 59 290.24 0.56 

60 295.25 0.61 60 295.25 0.61 

61 300.15 0.65 61 300.15 0.65 

62 305.28 0.64 62 305.28 0.64 

63 310.18 0.69 63 310.18 0.69 

64 315.49 0.6 64 315.49 0.6 

65 320.19 0.76 65 320.19 0.76 

66 325.23 0.71 66 325.23 0.71 

67 330.24 0.76 67 330.24 0.76 

68 335.32 0.8 68 335.32 0.8 

69 340.18 0.74 69 340.18 0.74 

70 345.08 0.78 70 345.08 0.78 

71 350.05 0.92 71 350.05 0.92 

72 355.22 0.93 72 355.22 0.93 

73 360.31 0.89 

74 365.71 0.93 74 365.71 0.93 

75 370.31 0.95 75 370.31 0.95 

76 375.07 1.04 76 375.07 1.04 

77 380.16 1.05 77 380.16 1.05 

78 385.24 1.08 78 385.24 1.08 

79 390.06 1.13 79 390.06 1.13 

80 395.05 1.1 80 395.05 1.1 

81 400.07 0.87 81 400.07 0.87 

82 404.36 0.98 82 404.36 0.98 

83 408.81 1.01 83 408.81 1.01 

84 412.39 1.16 

85 417.79 1.23 85 417.79 1.23 

86 420.3 1.31 86 420.3 1.31 

87 425.2 1.37 87 425.2 1.37 

88 429.82 1.42 88 429.82 1.42 

89 435.19 1.41 89 435.19 1.41 

90 440.01 1.5 90 440.01 1.5 

91 445.09 1.54 91 445.09 1.54 

92 449.96 1.64 92 449.96 1.64 

93 454.87 1.75 93 454.87 1.75 

94 459.95 1.92 94 459.95 1.92 

95 464.9 2.09 95 464.9 2.09 

96 470.04 2.19 96 470.04 2.19 

97 474.95 2.5 97 474.95 2.5 

98 479.85 2.8 98 479.85 2.8 

99 484.84 3.1 99 484.84 3.1 

100 489.88 3.38 100 489.88 3.38 

101 494.89 3.74 101 494.89 3.74 

102 499.75 4.08 102 499.75 4.08 

103 504.8 4.53 103 504.8 4.53 

104 509.84 4.9 104 509.84 4.9 

105 514.79 5.5 105 514.79 5.5 

106 519.88 5.9 106 519.88 5.9 

107 524.61 6.22 107 524.61 6.22 

108 529.82 6.72 108 529.82 6.72 

109 534.73 7.11 109 534.73 7.11 

110 539.86 7.6 110 539.86 7.6 
45

111 544.77 8.13 111 544.77 8.13 

112 549.89 8.58 112 549.89 8.58 

113 554.8 9.05 113 554.8 9.05 

114 559.42 9.5 114 559.42 9.5 

115 564.38 9.93 115 564.38 9.93 

116 569.29 10.43 116 569.29 10.43 

117 574.19 10.98 117 574.19 10.98 
CALIFORINIA

Area of 

Figure

Diablo Ranges. Santa Clara Valley

East Bay Plain

Niles Cone Santa Cruz Mtns

San Pablo

Bay

UC

SL

N

F

SLe

H

O

A

Fig 1

SILVER CREEK FAULT
SL-1

SL-2

SL-3

SL-4

SL-5

SL-6

East Bay Plain Seismic Transect

Fig. 2
0

10

20

30

40

50

Elevation (m)

0

500

10001500200025003000

Distance (m)

Geophone Location

-200

-100

0

100

200

Y-Variation (m )

0

500

10001500200025003000

Distance (m)

Geophone Location

0

10

20

30

40

50

Elevation (m)

0

500

10001500200025003000

Distance (m)

Shot Location

-200

-100

0

100

200

Y-Variation (m)

0

500

10001500200025003000

Distance (m)

Shot Location

0

50

100

150

200

Fold

0

250500750

10001250

Common Depth Point (CDP)

Fold

Southwest Northeast

Profile SL-1

A

B

C

D

E

Fig. 3
0

5

10

Elevation (m)

0

100200300400500600700

Distance (m)

Geophone Location

-50

-25

0

25

Y-Variation (m )

0

100200300400500600700

Distance (m)

Geophone Location

0

5

10

Elevation (m)

0

100200300400500600700

Distance (m)

Shot Location

-50

-25

0

25

Y-Variation (m)

0

100200300400500600700

Distance (m)

Shot Location

0

50

100

150

Fold

0

4080

120160200240280320

Common Depth Point (CDP)

Fold

West East

Profile SL-2

A

B

C

D

E

Fig. 4
05

10

Elevation (m)

0

100200300400500600700

Distance (m)

Geophone Location

-50

-2502550

Y-Variation (m )

0

100200300400500600700

Distance (m)

Geophone Location

05

10

Elevation (m)

0

100200300400500600700

Distance (m)

Shot Location

-50

-2502550

Y-Variation (m )

0

100200300400500600700

Distance (m)

Shot Location

0

50

100

150

Fold

0

100200300

Common Depth Point (CDP)

Fold

West East

Profile SL-3

ABCDE

Fig. 5
0

1

2

3

4

5

Elevation (m)

0

255075

100125150175200225250275

Distance (m)

Geophone Location

-20

-10

0

10

20

Y-Variation (m)

0

255075

100125150175200225250275

Distance (m)

Geophone Location

0

1

2

3

4

5

Elevation (m)

0

255075

100125150175200225250275

Distance (m)

Shot Location

-20

-10

0

10

20

Y-Variation (m )

0

255075

100125150175200225250275

Distance (m)

Shot Location

0

5

10

15

20

25

30

Fold

0

255075

100125

Common Depth Point (CDP)

Fold

Southwest Northeast

Profile SL-4

A

B

C

D

E

Fig. 6
-20

-10

0

10

20

Y-Variation (m )

0

50

100150200250300

Distance (m)

Geophone Location

0

2

4

6

Elevation

0

50

100150200250300

Distance (m)

Shot Location

-20

-10

0

10

20

Y-Variation (m)

0

50

100150200250300

Distance (m)

Shot Location

0

10

20

30

40

Fold

0

255075

100125

Common Depth Point (CDP)

Fold

0

1

2

3

4

5

6

Elevation (m)

0

50

100150200250300

Distance (m)

Geophone Location

Southwest Northeast

Profile SL-5

A

B

C

D

E

Fig. 7
05

10

Elevation (m)

0

100200300400500600

Distance (m)

ABCDE

Geophone Location

-25025

Y-Variation (m )

0

100200300400500600

Distance (m)

Geophone Location

05

10

Elevation (m)

0

100200300400500600

Distance (m)

Shot Location

-25025

Y-Variation (m)

0

100200300400500600

Distance (m)

Shot Location

0

50

100

150

Fold

0

50

100150200250

Common Depth Point (CDP)

Fold

Southwest Northeast

Profile SL-6

Fig. 8
Figure 9 is an oversize illustration and is a separate file.

View Figure 9 as a 68" x 13" file (of2006-1084_fig09.pdf; 2.6 MB)
Figure 10 is an oversize illustration and is a separate file.

View Figure 10 as a 46" x 20" file (of2006-1084_fig10.pdf; 14.3 MB)
Figure 11 is an oversize illustration and is a separate file.

View Figure 11 as a 68" x 16" file (of2006-1084_fig11.pdf; 9.3 MB)
7E1

13M4

13D7

7G12

14K12

6R2

14K2

14J2

14F1 14G2

12R1

12H1

0 0.5 1 Miles

0 0.5 1 Kilometers

EXPLANATION

Well with geophysical and

 lithologic log, and well number 

Well with lithologic log and 

 well number

Well projection line

Seismic profile and number

Hayward fault

Township boundary

SL-1

SAN

FRANCISCO

BAY

6R2

RANGE 3W RANGE 2W

S3 PIHSNWOT

7G12

Figure 12.

1-LS

SL-2

3-LS

4-LS

5-LS

6-LS

keerC ozneroL naS

088 I832 I085I088I832I-
Figure 13 is an oversize illustration and is a separate file.

View Figure 13 as a 70" x 16" file (of2006-1084_fig13.pdf; 14.3 MB)
 50

100

150

200

250

300

350

400

450

500

550

Elevation, in m

122 ̊22.5 ́ 122 ̊15 ́ 122 ̊07.5 ́ 122 ̊

37 ̊37.5 ́

37 ̊45 ́

37 ̊52.5 ́

0 2 4 6 8 10 KM

OAKLAND

San Leandro

Castro Valley

Hayward

Alameda

San Francisco Bay

San Leandro Hills

LAS TRAMPAS RIDGE

Gudde Ridge

Danville

BERKELEY

C

East Bay Plain

Seismic and 

Gravity Transects

C'

Fig. 14
0

1

23

45

6 Distance (km)

0.0

200

400

600

800

1000

1200

1400

1600

1800

2000 Depth (m)

Southwest San Francisco Bay

WashingtonAHayward Fault

ve

ChallengerSchoolI-880 FreewayI-238 FreewayE-14th StreetI-580 Freeway

Northeast

Franciscan Basement

(2.67)

Sediments

(2.2)

San Leandro Basin

-6

-4

-202468

10

12

14

Gravity (mgal)

Fig. 15

AB

Observed

Calculated
-15 -10 -5 0 5 10 15 Distance (km)

Depth, (km)

8

6

4

2

0 Offshore basin

Gravity (mgal) 

-40

-20

0

C

Magnetics (nT)

-150

0

150

300 C'

KJf

D=2.67

KJk Jb

Jgb

sp-px

Jgb

KJk

Jsv

Kr

Kjm

D=2.5

D=2.56

D=2.88, 

S=0.00117

D=3.03, S=0.00117

D=2.77

D=2.67

D=2.48, 

S=0.00117

D=2.57

D=2.35

D=2.4

Kjm

sp

SF Bay

Ts

Ko

Tn

D=2.20

D=2.48, 

S=0.00279

KJf

D=2.67

D=2.3

D=2.3

D=2.22

Qa

D=1.00 HF CF

0 2 4 6

2

0

1

Distance (km)

Depth (km)

Fig. 16

A

B

C
Figure 17a is an oversize illustration and is a separate file.

View Figure 17a as a 46" x 20" file (of2006-1084_fig17a.pdf; 35.1 MB)
0

200

400

600

800

1000

1200

1400 DEPTH (m)

0 500 1000 1500 2000 2500

Profile SL-1

line 1r3 f3 a1 v31 all: agc=500, fk=90,800,1,600/50, bp=15-30-400-800,n60,120 poststack: agc=500, bp=25-50-400-800, time to depth converted V31

DISTANCE (m)

VE 2:1

SW NE

Fig. 17b

B
0

Distance (m)

0

200

400

600

800

1000

1000 2000 3000 4000 5000 6000

1200

1400

1600

1800

2000 Depth (m)

Sedimentary Deposits

Franciscan Basement

Faults

Aquifers

Model 2 Basement

???

???

???

0

10

20

30

40

50

60

70

120

130

140

xx

xx

xx

xx

xx

xx

xx

xx

xx

xx

xx

W notgnihsa A ev

nairepseH A ev

kraP eladnedE

teertS ht41 .E

egdirB tooF

eganiarD

RR

tfihS eniL

egde 088Iegde 088I

V adanarG aiV adanarG ai

RRRR

832-I

egdE nretsaE

teertS ht41E

.tS ospylaC

085-I

tfihS eniL

W notgnihsa A ev

nairepseH A ev

San Lorenzo High School

kraP eladnedE

teertS ht41 .E

Well 3S3W-13D7Well 3S3W-12R1

Well 3S3W-7E1

W W2S3 lle 21G7-

W W2/S3 lle 6R2-

Wel 3S3W13M4

Wel 3S3W14G2

Challenger SchoolBridge

egde 088Iegde 088I

V adanarG aiV adanarG ai

RRRR

832-I

egdE nretsaE

teertS ht41E

.tS ospylaC

085-I

tfihS eniL

Well 3S3 W-14K2

Well 3S3W-14J2

Well 3S3 W-14F1

-50 0 50 100

DEPTH

0

100

200

300

400

500

600

3S/2W7G12

34.7

?

?

30.48

61.0

91.5

122.0

152.5

183.0

0 100 3S3W13D7

13.3

30.48

61.0

91.5

122.0

152.5

183.0

213.5

244.0

274.5

0

100

200

400

500

600

700

800

900

1000

300

0 80

SNOR 6.5

3S3W13M4

30.48

61.0

91.5

122.0

152.5

183.0

213.5

244.0

274.5 N

Lateral Shift in Profile

3S2W-14K2 3S3W-14G2 3S2W-14J2

3S3W-12R1

Static Water 

Level

Depth (m)

0

10

20

30

40

50

60

70

80

90

100

110

120

130

140

150

160

170

180

190

200

210

220

230

240

250

260

270

280

290

300

310

3S3W-13D7

Depth (m)

0

10

20

30

40

50

60

70

80

90

100

110

120

130

140

150

160

170

180

190

200

35/2W-7G12

0

100

200

300

400

500

600

700

0

W notgnihsa A ev

nairepseH A ev

kraP eladnedE

teertS ht41 .E

egdirB tooF

eganiarD

RR

tfihS eniL

egde 088Iegde 088I

V adanarG aiV adanarG ai

RRRR

832-I

egdE nretsaE

teertS ht41E

.tS ospylaC

tfihS eniL

W notgnihsa A ev

nairepseH A ev

San Lorenzo High School

kraP eladnedE

teertS ht41 .E

Well 3S3W-13D7Well 3S3W-12R1

Well 3S3W-12H1

Well 3S3W-7E1

W W2S3 lle 21G7-

W W2/S3 lle 6R2-

Wel 3S3W13M4

Wel 3S3W14G2

Challenger SchoolBridge

egde 088Iegde 088I

V adanarG aiV adanarG ai

RRRR

832-I

egdE nretsaE

teertS ht41E

.tS ospylaC

tfihS eniL

Well 3S3 W-14K2Well 3S3 W-14K12 Well 3S3 W

Well 3S3W-14J2

Well 3S3 W-14F1

Profile SL-1 Profile SL-2 Profile SL-3 Profile SL-4 Profile SL-5 Profile SL-6

3S/2W-7E1

3S/2W7G12

0 100 3S3W13D7 3S3W13M4

Lateral Shift in Profile

3S3W-12R1

3S3W-13D7 3S2W-7E1

SW NE

Sediments

Franciscan

Basement

Explanation

f

0 50 100

3S/2W-7E1

300

400

500

600

700

800

9000 100

200

34.7

30.48

61.0

91.5

122.0

152.5

183.0

213.5

244.0

274.5

80

90

100

110

SF Bay

Near-Surface

Fault Zone Near-Surface

Fault Zone

Near-Surface

Fault Zone

Near-Surface

Fault Zone

Near-Surface

Fault Zone ??

3S2W-6R2

0

10

20

30

40

50

60

70

80

90

100

110

120

130

140

150

160

170

180

190

200

210

220

230

240

250

260

270

280

290

300

3S2W-7E1

Fig.18

?

?

?

?

?

?

?

?

?

?

?

?
Figure 19 is an oversize illustration and is a separate file.

View Figure 19 as a 70" x 17" file (of2006-1084_fig19.pdf; 15.8 MB)

Figure 21 is an oversize illustration and is a separate file.

View Figure 21 as a 50" x 20" file (of2006-1084_fig21.pdf; 16 MB)
0

200

400

600

800

1000

2000

3000

4000 DEPTH (m)

0 500 1000 1500 2000 2500

line 1r3 f3 a1 v31 all: agc=500, fk=90,800,1,600/50, bp=15-30-400-800,n60,120 poststack: agc=500, bp=25-50-400-800, time to depth converted V31

DISTANCE (m)

Fig. 22

SW NE Profile SL-1