GEOLOGICAL SURVEY CIRCULAR 795 

Estimation of Ground Motion Parameters 

Estimation of Ground Motion Parameters 

By David M. Boore, William B. Joyner, 

Adolph A. Oliver Ill, and Robert A. Page 

GEOLOGICAL SURVEY CIRCULAR 

Prepared on behalf of the Nuclear Regulatory Commission 

1978 

795 
United States Department of the Interior 

CECIL D. ANDRUS, Secretary 

Geological Survey 

H. William Menard, Director 

Free on application to Branch of Distribution, U.S. Geological Survey, 12 0 0 South Eads Street, Arlington, VA 2 2 2 0 2 
CONTENTS 

Page 

Abstract----------------------------------------------------------------- 1 

Introduction------------------------------------------------------------- 1 

Data characteristics and methods of presentation------------------------- 1 

All earthquakes---------------------------------------------------------- 5 

San Fernando earthquake-------------------------------------------------- 17 

Previously published curves for peak acceleration------------------------ 23 

Estimation of peak parameters at short distances------------------------- 25 

References cited--------------------------------------------------------- 26 

Statistical parameters--------------------------------------------------- 30 

Strong-motion data------------------------------------------------------- 32 

TABLE 

Table l. Sources of data used in assigning magnitudes and station 

distances---------------------------------------------------- 2 

ILLUSTRATIONS 

Figure 1-48. Graphs showing: 

1. Peak horizontal acceleration versus distance 

to slipped fault for magnitude range 5.0-

5.7-------------------------------------------- 6 

2. Peak horizontal acceleration versus distance 

to slipped fault for magnitude range 6.0-

6.4-------------------------------------------- 7 

3. Peak horizontal acceleration versus distance to 

slipped fault for magnitude range 7.1-7.6------ 7 

4. Comparison of 70 percent prediction intervals for 

peak horizontal acceleration for all three 

magnitude classes------------------------------ 7 

5. Peak horizontal velocity versus distance to 

slipped fault for magnitude range 5.3-5.7------ 8 

6. Peak horizontal velocity versus distance to 

slipped fault for magnitude 6.4---------------- 8 

7. Peak horizontal velocity versus distance to 

slipped fault for magnitude range 7.1-7.2------ 8 

8. Comparison of 70 percent prediction intervals for 

peak horizontal velocity for three magnitude 

classes---------------------------------------- 9 

9. Peak horizontal displacement versus distance to 

slipped fault for magnitude range 5.3-5.7------ 9 

10. Peak horizontal displacement versus distance to 

slipped fault for magnitude 6.4---------------- 9 

11. Peak horizontal displacement versus distance to 

slipped fault for magnitude range 7.1-7.2------ 10 

12. Comparison of 70 percent prediction intervals for 

peak horizontal displacement for three 

magnitude classes------------------------------ 10 

13. Duration versus distance from slipped fault for 

recordings from small structures.-------------- 10 

14. Peak vertical acceleration versus distance to 

slipped fault for magnitude range 5.0-5.7------ 11 

15. Peak vertical acceleration versus distance to 

slipped fault for magnitude range 6.0-6.4------ 11 

iii 
ILLUSTRA liONS, CONTINUED 

Page 

16. Peak vertical acceleration versus distance to 

slipped fault for magnitude range 7.1-7.6------ 11 

17. Peak vertical velocity versus distance to slipped 

fault for magnitude range 5.3-5.7-------------- 12 

18. Peak vertical velocity versus distance to slipped 

fault for magnitude 6.4------------------------ 12 

19. Peak vertical velocity versus distance to slipped 

fault for magnitude range 7.1-7.2-------------- 12 

20. Peak vertical displacement versus distance to 

slipped fault for magnitude range 5.3-5.7------ 13 

21. Peak vertical displacement versus distance to 

slipped fault for magnitude 6.4---------------- 13 

22. Peak vertical displacement versus distance to 

slipped fault for magnitude range 7.1-7.2------ 13 

23. Peak horizontal acceleration versus distance to 

slipped fault for magnitude range 5.0-5.7 

including data from both large and small 

structures------------------------------------- 14 

24. Peak horizontal acceleration versus distance to 

slipped fault for magnitude range 6.0-6.4 

including data from both large and small 

structures------------------------------------- 14 

25. Peak horizontal acceleration versus distance to 

slipped fault for magnitude range 7.1-7.6 

including data from both large and small 

structures------------------------------------- 14 

26. Peak horizontal velocity versus distance to 

slipped fault for magnitude range 5.3-5.7 

including data from both large and small 

structures------------------------------------- 15 

27. Peak horizontal velocity versus distance to 

slipped fault for magnitude 6.4 including data 

from both large and small structures----------- 15 

28. Peak horizontal velocity versus distance to 

slipped fault for magnitude range 7.1-7.2 

including data from both large and small 

structures------------------------------------- 15 

29. Peak horizontal displacement versus distance to 

slipped fault for magnitude range 5.3-5.7 

including data from both large and small 

strucutures------------------------------------ 16 

30. Peak horizontal displacement versus distance to 

slipped fault for magnitude 6.4 including data 

from both large and small structures----------- 16 

31. Peak horizontal displacement versus distance to 

slipped fault for magnitude range 7.1-7.2 

including data from both large and small 

structures------------------------------------- 16 

32. Peak horizontal acceleration versus distance to 

slipped fault at soil sites, San Fernando 

earthquake------------------------------------- 18 

33. Comparison of mean regression lines and 70 percent 

prediction intervals for large and small 

structures for peak horizontal acceleration at 

soil sites, San Fernando earthquake------------ 18 

34. Peak horizontal velocity versus distance to 

slipped fault at soil sites, San Fernando 

earthquake------------------------------------- 19 

iv 
ILLUSTRATIONS, CONTINUED 

Page 

35. Comparison of mean regression lines and 70 percent 

prediction intervals for large and small 

structures for peak horizontal velocity at 

soil sites, San Fernando earthquake------------ 19 

36. Peak horizontal displacement versus distance to 

slipped fault at soil sites, San Fernando 

earthquake------------------------------------- 19 

37. Comparison of mean regression lines and 70 percent prediction intervals for large and small 

structures for peak horizontal displacement at 

soil sites, San Fernando earthquake------------ 20 

38. Peak horizontal acceleration recorded at base of 

small structures versus distance to slipped 

fault, San Fernando earthquake----------------- 20 

39. Comparison of mean regression lines and 70 percent 

prediction intervals for rock and soil sites 

for peak horizontal acceleration recorded at 

base of small structures, San Fernando 

earthquake------------------------------------- 20 

40. Peak horizontal velocity recorded at base of small 

structures versus distance to slipped fault, 

San Fernando earthquake------------------------ 21 

41. Comparison of mean regression lines and 70 percent 

prediction intervals for rock and soil sites 

for peak horizontal velocity recorded at base 

of small structures, San Fernando earthquake------------------------------------------ 21 

42. Peak horizontal displacement recorded at base of 

small structures versus distance to slipped 

fault, San Fernando earthquake----------------- 21 

43. Comparison of mean regression lines and 70 percent 

prediction intervals for rock and soil sites 

for peak horizontal displacement recorded at 

base of small structures, San Fernando earthquake------------------------------------------ 22 

44. Azimuthal dependence of peak horizontal acceleration recorded at base of small structures, San 

Fernando earthquake---------------------------- 22 

45. Azimuthal dependence of peak horizontal velocity 

recorded at base of small structures, San 

Fernando earthquake---------------------------- 22 

46. Azimuthal dependence of peak horizontal displacement recorded at base of small structures, San 

Fernando earthquake---------------------------- 23 

47. Proposed relations of peak horizontal acceleration 

to distance from slipped fault for magnitude 

6.6 earthquake--------------------------------- 24 

48. Proposed relations of peak horizontal acceleration 

to distance from slipped fault for magnitude 

7.6 earthquake--------------------------------- 24 

v 

Estimation of Ground Motion Parameters 

By David M. Boore, William B. Joyner, Adolph A. Oliver Ill, and Robert A. Page 

ABSTRACT 

Strong motion data from western North 

America for earthquakes of magnitude greater 

than 5 are examined to provide the basis for 

estimating peak acceleration, velocity, 

displacement, and duration as a function of 

distance for three magnitude classes. A 

subset of the data (from the San Fernando 

earthquake) is used to assess the effects of 

structural size and of geologic site 

conditions on peak motions recorded at the 

base of structures. Small but statistically 

significant differences are observed in peak 

values of horizontal acceleration, velocity 

and displacement recorded on soil at the base 

of sma 11 structures compared with values 

recorded at the base of large structures. The 

peak acceleration tends to be less and the 

peak velocity and displacement tend to be 

greater on the average at the base of 1 arge 

structures than at the base of small 

structures. In the distance range used in the 

regression analysis (15-100 km) the values of 

peak horizontal acceleration recorded at soil 

sites in the San Fernando earthquake are not 

significantly different from the values 

recorded at rock sites, but values of peak 

horizontal velocity and displacement are 

significantly greater at soil sites than at 

rock sites. 

Some consideration is given to the 

prediction of ground motions at close 

distances where there are insufficient 

recorded data points. As might be expected 

from the lack of data, published relations for 

predicting peak horizontal acceleration give 

widely divergent estimates at close distances 

(three well known relations predict 

accelerations between 0.33 g to slightly over 1 g at a distance of 5 km from a magnitude 6.5 

earthquake). After considering the physics of 

the faulting process, the few ava i1 able data 

close to faults, and the modifying effects of 

surface topography, at the present time it 

would be difficult to accept estimates less 

than about 0.8 g , 110 cm/s, and 40. em, 

respectively, for the mean values of peak 

acceleration, velocity, and displacement at 

rock sites within 5 km of fault rupture in a magnitude 6.5 earthquake. These estimates can 

be expected to change as more data become 

avail able. 

INTRODUCTION 

Peak horizontal acceleration is commonly 

used to scale response spectra or ground 

motion -time histories for use in earthquake 

resistant design, particularly for nuclear 

power plant facilities (Newmark, Blume, and 

Kapur, 1973). Methods have also been proposed 

(Newmark and Hall, 1969) for constructing 

design spectra using three peak parameters 

--hori zonta 1 acce 1 erati on, ve 1 oc ity, and 

displacement--the advantage of using all three 

parameters being that together they convey 

some information concerning the shape of the 

spectrum as we 11 as the amp 1 itude 1 eve 1. In 

this report we present the analysis of a large 

number of earthquake data to provide the basis 

for estimating the peak acceleration, 

velocity, and displacement and duration of 

shaking for a hypothetical earthquake of a 

prescribed magnitude at a prescribed distance 

from the causative fault. This work is a 

continuation of that reported by Page, Boore, 

Joyner, and Coulter (1972) and by Page, Boore, 

and Dieterich (1975). 

It is not our purpose to advocate the use 

of peak parameters in sea 1 i ng design motions. 

We look forward ultimately to the development 

of new methods for prescribing design motions, 

methods more firmly based in the physics that 

governs faulting and wave propagation. 

Pending the development of such methods, we 

recognize widespread current practice and 

attempt to present the available strong motion 

data in a compact and useful form for 

estimating peak parameters. 

Aknowledgments. -- We are grateful to R. P. 

Maley for assistance in obtaining information 

on strong-motion recording site conditions and 

to A. G. Brady for unpub 1 ished strong motion 

data. 

DATA CHARACTERISTICS 

AND METHODS OF PRESENTATION 

Sources of data. -- The data set includes 204 

recordings from 19 earthquakes and is 1 isted 

in the tab 1 e of 11 Strong motion data 11 (end of 

report). The primary source of acce 1 erati on 

data is volume I of the series 11 Strong-Motion 

Earthquake Acce 1 erograms 11 pub 1 i shed under the 

direction of D. E. Hudson by the Earthquake 

Engineering Research Laboratory of the 

California Institute of Technology; values of 
velocity, displacement, and duration came from 

volume II of the same series. We used volume 

I for acceleration because volume II gives 

data at equal time intervals of 0.02 s, which 

tends to bias the peak acceleration toward 

lower values. A few of the acceleration data 

came from other sources listed in the table of 11 Strong-motion data 11 , principally u.s. Earth- quakes~ an annual publication of the U. S. Department of Commerce. 

Distances. -- In a 11 cases the distance used 

is the shortest distance between the surface 

of fault slippage and the recording point. This would clearly be the preferred measure of 

distance if radiation were uniform over the 

surface and if the surface were known. The 

second condition is sometimes not met· the 

first is probably never met. Other me~sures of distance have been used in strong motion 

data analysis, particularly epicentral 

distance, hypocentral distance, and distance 

from the center of energy release. The use of 

epicentral distance or hypocentral distance 

has the advantage that these measures are more 

commonly known and special studies are not 

required to determine them. In some cases, 

however, these measures are clearly inappropriate, as for a long fault rupture 

with the epicenter at one end and recording 

stations at the other. The Parkfield, 

California, earthquake of 1966 provides an 

example of such a situation. The use of 

distance to the center of energy release is a 

way of avoiding the assumption of uniform 

radiation over the rupture surface, but for 

long ruptures this measure, too, may be 

inappropriate. In our opinion the best choice 

for genera 1 purposes is the c 1 osest distance 

to the rupture surface, but the uncertainties 

resulting from nonuniform radiation over the 

surface should be kept in mind. An 

illustration of those uncertainties, is 

provided by the Pacoima Dam recording of the 

San Fernando earthquake of 1971. On that 

record the source for peak ve 1 oc ity and for 

the peak acceleration are different points on 

the fault, separated by perhaps 20 km, neither 

one of which is the closest point to the 

instrument (Hanks, 1974; Bouchon and Aki 

1977). ' 

With a few exceptions the location of the 

rupture surface has been inferred from the 

aftershock distribution. For the Imperial 

Valley, California, earthquake of 1940 the 

distance used is chosen in accordance with the 

interpretations of Richter {1958) and Trifunac 

and Brune (1970). For the Hebgen Lake, 

Montana, earthquake of 1959, the distance used 

is the epicentral distance of the main shock, 

and for the Puget Sound earthquake of 1949, 

the distance used is the hypocentra 1 distance 

of the main shock, assuming a minimum focal 

depth of 45 km. Sources of data used in 

estimating station distances are include~ in 

table I. 

Table 1. --Sources of da in used in assigning magnitudes and station distances 

Earthquake 

Imperial Va 11 ey, California----- 5 

Puget Sound, Washington--------- 4 

Kern County, California--------- 7 

Daly City, California----------- 3 

Hebgen Lake, Montana------------ 8 

Parkfield, California----------- 6 

Fairbanks, Alaska--------------- 6 

19 40 

13 49 

21 52 

22 57 

18 59 

28 66 

21 67 

2 

Sources 

Trifunac and Brune (1970); 

Trifunac (1972); Richter 

( 1958). 

Nuttli (1952); Page, Boore, 

Joyner, and Coulter (1972). 

Richter (1958); Page, Boore, 

Joyner, and Coulter (1972); 

Bolt (1978). 

Tocher (1959); Cloud (1959). 

Tocher (1962); Page, Boore, 

Joyner, and Coulter (1972). 

McEvilly and others (1967); 

Lindh and Boore (1973); 

Trifunac and Udwadia (1974); 

A. G. Lindh (oral commun., 

1976) . 

Gedney and Berg (1969). 
Table 1.--Sources of da 1a used in assigning magnitudes and station distances--Continued 

Date (GMT) 

Earthquake Month ~ Year Sources 

Borrego Mountain, California---- 4 9 68 

Santa Rosa, California---------- 10 2 69 

Allen and Nordquist (1972); 

Hami 1 ton ( 1972). 

Steinbrugge and others (1970); 

Unger and Eaton (1970); J. D. 

Unqer and J. P. Eaton 

(written commun., 1976). 

Lytle Creek, California---------- 9 12 70 T. C. Hanks (written commun., 

1971). 

San Fernando, California--------- 2 9 71 Allen, Hanks and Whitcomb 

(1973); Allen and others 

(1971); R. L. Wesson (written 

commun., 1974). 

Bear V a 11 ey , California---------- 2 24 

Sitka, Alaska-------------------- 7 30 

Managua, Nicaragua------------ 12 23 

Point ~1ugu, California-------- 2 21 

Bear Va 11 ey, California------- 11 28 

Oro vi 11 e, California---------- 8 

Ferndale, California---------- 6 7 

In order to avoid obscuring the 

attenuation relation, we generally exclude 

data where the uncertainty in distance is 

large. Following Page, Boore, Joyner, and 

Coulter {1972), we classify the distances as 

A, B, or C, according to the uncertainty (less 

than 2 km, 2 to 5 km, and 5 to 25 km, 

respectively). C quality data are only used 

for the magnitude 7. 1 Puget Sound earthquake 

and the magnitude 7.1 Hebgen Lake earthquake. 

In the plots to follow, the class A, B, or C 

is indicated by the size of the symbol, the 

largest for class A and the smallest for class 

c. 

The assignment of distances for the 

Parkfield earthquake deserves special 

mention. Originally it was believed that the 

3 

72 

72 

72 

73 

74 

75 

75 

Ellsworth (1975). 

Page and Gawthrop (1973); 

W. H. Gawthrop and R. A. 

Page (unpub. data). 

Dewey and others (1973); Ward 

and others (1973); Knudson 

and Hansen, A. (1973). 

Ellsworth and others (1973); 

Boore and Stierman (1976); 

Stierman and Ellsworth (1976). 

Person (1975); W. H. K. Lee 

(written commun., 1976). 

Bufe and others (1976); Lahr 

and others (1976). 

Nason and others (1975); 

Stewart Smith (written 

commun., 1976). 

rupture associated with the Parkfield 

earthquake extended a 1 ong the San Andreas 

fault far enough to the southeast so that it 

pas sed within 80 meters of station 2 of the 

Cholame-Shandon array (Cloud and Perez, 

1967). Lindh and Boore ( 1973), however, 

presented evidence that, at the time of the 

earthquake, no significant displacement 

occurred beyond a point 7 km northwest of 

station 2. Modeling studies by Trifunac and 

Udwadia (1974) tend to confirm the 

interpretation of Lindh and Boore and we 

follow it in this report. 

Classification of data. -- We have divided the 

data into classes in accordance with 

magnitude, site geology, and size of 

associated structure. The data were divided 
into three magnitude classes (5.0-5.7, 

6.0-6.4, and 7. 1-7.6) on the basis of the 

Richter local magnitude (Richter, 1958), if 

available; otherwise surface wave magnitude is 

used. Sources of data for assigning magnitudes are included in table I. The 

Imperial Valley earthquake is assigned a 

magnitude of 6.4 in accordance with a 

determination by Trifunac and Brune (1970) and 

in contrast to the value 7.1 that is commonly given. Kanamori and Jennings (1978) have recently 

developed a method of determining Richter 

local magnitude from strong motion records. 

Their magnitude assignments are in general 

agreement with ours. The largest difference 

is for the Puget Sound earthquake of 1949 for 

which their value is 6.5 in contrast with our 

value of 7. 1. 

We assign recording sites to one of two 

categories, 11 rock 11 or 11 Soil 11 , by applying our 

best judgment to the available site 

descriptions. We assign stations to the rock 

category if they are underlain by material 

described by such terms as .. granite, .. 11 diorite,.. 11 gneiss,.. "chert,.. "graywacke," 

limestone," 11 Sandstone," 11 Siltstone,.. or 11 Shale." Stations are assigned to the soil 

category if they are underlain by sufficient 

thickness of material described by such terms 

as "alluvium, .. "sand," 11 gravel, .. "clay, .. 

"silt," "mud," "fill," or "glacial outwash." 

If we judge from the site description that 

soil material overlying rock is less than 4 to 

5 meters thick we assign the site to the rock 

category. Sources for site descriptions are 

given in the table of "strong-motion data ... Because considerable uncertainty and ambiguity attends the geological classification of 

recording sites, we do not even suggest 

conclusions that rely on the validity of the 

classification of a single station. We are 

concerned only with trends revealed by 

comparing whole classes of data. 

Many of the data come from the basements 

or ground floors of buildings or from the 

abutments of dams. In the analysis of 

strong-motion data, it is commonly assumed 

that the influence of the structure on the 

motion of the base can be ignored and that the 

data as recorded represent free-fie 1 d ground 

motion. We have attempted a limited test of 

this assumption by classifying recording sites 

in accordance with the size of the associated 

structure; class 1 for sites at the base of 

one- or two-story buildings and class 2 for 

sites at the base of ta 11 er bu i1 dings or on 

dam abutments. Comparison of the two classes 

using data from the San Fernando earthquake is 

described in a subsequent section. 

With regard to velocity and displacement, 

one would expect the data from small 

structures to be more representative of 

free-field motion. The transfer functions 

re 1 ati ng motion at the base of structures to 

4 

free-field motion tend toward unity for 

frequencies that are small compared to the 

fixed-base natural frequencies of the 

structure. (For examples of theoretical and 

empirical transfer functions see Duke and 

others, 1970, and Crouse and Jennings, 1975). 

The small structures have natural frequencies 

mostly in the range of 2 to 10 Hertz, which is 

significantly above the range of frequencies 

dominant in the velocity and displacement time 

histories. The case of acceleration is more 

complicated. For large buildings the dominant 

frequencies will be higher than the structural 

resonant frequency, and the transfer functions 

tend to fall below unity. The natural 

frequencies of the sma 11 structures, however, 

are in the same range as the frequencies 

dominant in the acceleration time histories, 

and the effect of the structure may be to 

raise or lower the acceleration depending on 

the spectrum of the earthquake and the details 

of the transfer function. We would expect the 

acceleration values for the large structures 

to be systematically biased downward, but the 

values for the smaller structures may be 

either increased or decreased. In fact, our 

comparison of San Fernando data shows sma 11 er 

accelerations on the average for the large 

structures. Our main emphasis, therefore, is 

p 1 aced on the data from the sma 11 structures 

as a basis for estimating free-field motion, 

but for the hori zonta 1 component data we a 1 so 

provide plots and regression parameters for 

the whole data set. 

Geographical distribution. -- In an attempt to 

keep the data sample reasonably homogeneous, 

only records obtai ned in the western part of 

North America were included. In order to 

avoid bias from the extremely dense cluster of 

instruments in downtown Los Angeles a special selection procedure was used in the area 

between latitude 34.000 and 34.110 N. and 

longitude 118.240 and 118.450. Within 

each of the two geologic site categories, only 

one recording per earthquake was allowed for 

each structure category, making a maximum of 

four possible recordings from the designated 

area for one earthquake. Selection was made 

by choosing the station with the smallest 

identification number of all eligible 

stations. In the table "strong-motion data", 

stations so chosen are denoted by an asterisk. 

Presentation of data. -- Peak horizontal 

acceleration, velocity, and displacement data 

are plotted against distance on log-log grids for each magnitude class. The peak values for 

horizontal motion are taken from the component 

with the larger peak. Duration values are 

plotted against distance on a linear grid. 

The measure of duration used is the time 

interval between the first and last horizontal 

acceleration peaks equal to or greater than 

0.05 g. The value is taken from the horizontal 

component that gives the larger value. This 

is the definition used by Page, Boore, Joyner, 
and Coulter {1972}. It is a relatively crude 

measure, but it is simple to determine and is 

of some value in characterizing ground 

motion. Peak vertical acceleration, velocity, and displacement are plotted on log-log grids in the same way as the horizontal data. 

Statistics. -- The nature of the strong 

motion data set is not such as to bear the 

weight of elaborate or subtle statistical 

inferences. For that reason we emphasize 

plots showing the individual data points. We 

do, however, indulge in statistical analysis 

to the extent of determining least-squares 

straight lines relating the logarithm of the 

peak parameters to the logarithm of distance 

and determining the confidence limits for the 

prediction of a single value of the dependent variable (Dixon and Massey, 1957). The 

equations used in the statistical analysis and 

the coefficients for the regre$sion lines 

shown in the figures are contained in the .. statistical parameters .. section (end of the 

report). 

We have attempted to avoid bias in the 

regression analysis by not including points 

that are either too close or too far from the 

fault. In the first case the data are too 

sparse to indicate the proper functional form 

for the regression and in the second the data 

set is i ncomp 1 ete because not a 11 instruments 

were triggered by the motion. For small 

structures the data used in our regression calculations are contained within the ranges 5-30, 15-55, and 40-150 km for magnitude classes 5.0-5.7, 6.0-6.4, and 7. 1-7.6, 

respectively. For the San Fernando earthquake the range is 15-100 km. For the whole data 

set, including both large and small 

structures, the ranges are the same as for the 

small structures except for magnitude class 

6.0-6.4 for which the range is 10-55 km. 

The straight lines obviously fit the data 

as well as would any simple relation. 

Curvature that might be caused by ane 1 ast i c 

attenuation is completely obscured by the 

scatter in the data. 

The scatter is approximately constant 

independent of distance. This constancy 

suggests that the decision was correct to fit 

a straight line relation to the logarithms of 

variables rather than fit a power law relation 

to the variables themselves. 

ALL EARTHQUAKES 

Data for all the earthquakes are presented in this section, with emphasis on the data 

from small structures because, for reasons 

given previously, we consider those data a 

better guide to free-field motion. In the 

succeeding section data from the San Fernando 

earthquake are examined to assess the effect 

of structure and the effect of local site 

geology. 

5 

Horizontal acceleration. -- Peak horizontal 

acceleration data from the small structures 

for the three magnitude classes (figs. 1-3) show that accelerations clearly increase with 

magnitude in those distance ranges for which 

there is overlap between the classes. The 

relations among the magnitude classes are 

summarized in figure 4, which shows the 

overlap of the 70 percent prediction intervals. The scatter for the magnitude 5.0-5.7 data is significantly greater than 

that for either of the other two classes. 

This difference may arise partly because a 

number of different earthquakes contribute 

substantially to the data set for the 5.0-5. 7 

class, whereas the 6.0-6.4 class is dominated 

by data from the 1971 San Fernando earthquake and the 7.1-7.6 class is dominated by data 

from the 1952 Kern County earthquake. 

The rate of attenuation of acceleration 

with distance for the magnitude 5.0-5.7 class 

appears to be greater than indicated by the 

slope of -0.9 for the mean regression line in 

figure 1. This is suggested by the systematic tendency for the data points at distances 

beyond 30 km to 1 i e be 1 ow an extension of the 

mean regression line. As previously explained, we have chosen to exclude from the 

regression analysis data beyond the distance 

at which all instruments can be presumed to 

have triggered. The distance range for which 

a reasonably complete data set is currently available is not adequate for a good 

determination of slope; the standard error of 

the slope for the magnitude 5.0-5.7 class is 

0. 5. Judging from the data at greater distances, the slope of -1.2 + 0.3 for the 

mean line for the magnitude -6.0-6.4 class 

(fig. 2) appears to be a better estimate of 

the rate of attenuation to distances of at 

least 100 km for that data set. The slope of 

-2.0 + 0.4 for the magnitude 7.1-7.6 class 

(fig.- 3} may overestimate the rate of 

attenuation, but the data are scanty. 

Horizontal velocity. -- The peak hori zonta 1 

velocity data from the small structures for 

the three magnitude classes are presented in 

figures 5-7. There are fewer velocity than 

acceleration points because integrations were 

not available for all the accelerograms. There are so few points for the magnitude 7.1-7.2 class that regression lines are not 

included on figure 7. As with acceleration, 

the peak velocity at a given distance tends to 

increase with magnitude (fig. 8}. 

The slope of -0.6 + 0.4 for the mean 

regression lines for the magnitude 6.4 data 

appears to underestimate the rate of 

attenuation if one considers the San Fernando 

data (described in the next section), which 

give better determinations because the 

distance range extends to 100 km. We were 
confident that all the instruments out to 100 

km were triggered in the San Fernando 

earthquake, but this confidence does not apply 

to the whole magnitude class. 

Horizontal displacement. -- The peak horizontal displacements for the three 

magnitude classes are given in figures 9-ll. 

The scatter of the data is 1 arger than for 

acceleration or velocity in each magnitude class, and the standard errors of the slopes 

of the mean regression 1 i nes exceed 0. 5. The 

displacements are derived from double 

integration of high-pass filtered accelerograms and therefore represent high-pass 

filtered versions of the true ground 

displacement. The longer periods, which are 

contaminated by processing noise, are removed. 

Hanks (1975) has studied the errors in 

displacement records derived by double 

integration of filtered accelerograms. He 

found that the errors are typically less than 

1 em in the period range 5-8 s, 1-2 em at 

periods near 10 s, and 2-4 em in the period 

range 10-15 s. These findings raise the 

possibility that some of the low-amplitude data points in figures 9 and 10 may be 

influenced by noise and may represent upper 

bounds to the actual ground displacement. The 

character of some of the low amplitude records 

resembles noise rather than signal. 

Nevertheless, we have proceeded in the 

analysis with the understanding that the 

results may be compromised to some extent by the effect of noise on the weaker motions. 

The over 1 ap of the 70 percent prediction 

intervals for the three magnitude classes is 

shown in figure 12. The amplitude increases 

with magnitude. 

Duration. -- A 11 the hori zonta 1 duration data 

are plotted in figure 13. Symbols for zero 

duration indicate that the peak acceleration 

on the record is less than 0.05 g. The upper 

and lower rows of x•s represent zero durations 

for magnitude classes 6.4 and 5.3-5.7, 

respectively. 

Two features of the data are obvious and 

expected. The durations increase with 

increasing magnitude and decrease with 

increasing distance. The influence of 

magnitude reflects the larger fault size and 

consequent increased time of rupture as 

magnitude is increased. The effect of 

distance results from the general decrease in 

amplitude with distance, given that we have 

used a fixed amplitude in the definition of 

duration. Had we defined duration in terms of 

some fraction of the peak amplitude, it is 

likely that the spreading apart of the seismic 

phases would have led to an increase of 

duration with distance. 

6 

Vertical data. -- The vertical data are 

presented in the same manner as the horizontal 

data. Peak vertical accelerations for the 

three magnitude classes are shown in figures 14-16; peak vertical velocities are shown in 

figures 17-19; and peak vertical displacements 

are shown in figures 20-22. 

The whole data set. -- For the horizontal 

components, data from both large and small 

structures taken together are presented in 

figures 23 through 31. 

1.0 

0> 

z 

z' 

0 

i= 

<{ 

0::: 

w 0.1 X _,J 

w 

u 

u 

<{ 

EXPLA~~ _,J 

~ ~ z x<> ~ 

0 X 

N 0 

0.01 x<> 02 

0 X Rock site xo I <> 0 0 Soil site ox 

<> 0 

0 .00 1 L------l'--.L..-.1.---L--........ ..I..L---L---'-_._. .......... ~-::-__..-V'____._. 

1 10 

DISTANCE, IN KILOMETERS 

Figure 1. Peak horizontal acceleration versus 

distance to slipped fault for magnitude 

range 5.0-5.7 recorded at base of small 

structures. Center line is mean regression line. Outer pair of lines represents 95 

percent prediction interval; inner pair, 70 

percent prediction interval. Length of 

lines represents distance interval 

considered in regression. analysis. Uncertainty in distance 1s inversely related to symbol size (see text). 
0> 

z 

<> 

z 

0 

i= 

~~0 <( 

Ck:: 

w 0.1 .....I 

w 

u 

u 

<( 

.....I 

$ 

0 

z ~ N X<><> 

Ck:: 0.01 OS( 0 

I oe 

DISTANCE, IN KILOMETERS 

Figure 2. Peak horizontal acceleration versus 

distance to slipped fault for magnitude 

range 6.0-6.4 recorded at base of small 

structures. Symbols and curves same as in 

figure 1. 

MAGNITUDE 7.1-7.6 SMALL STRUCTURES 

1.0 

0> 

z 

z' 

0 

i= 

<( 

Ck:: 

w 0.1 .....I 

w 

u 

u 

<( X 

.....I 

<( 

tz 0 

0 

N 

Ck:: 0.01 

0 

I 

0.00 1 L___j____j___l_...L..L,U....L.L--!____..J.........J...~..L..W..l...---J_..J~ 

100 1 10 

DISTANCE, IN KILOMETERS 

7 

0> 

z 

z 

0 

i= 

<( 

Ck:: 

w 

.....I 0.1 w 

u 

u 

<( 

.....I 

$ 

z 

0 

N 

~ 0.01 

I 

5.0-5.7 

0.00 1 L,_____...L____..J.........J...-1..,.;L...L..I....L.L..-____..JL--~-J,....J.~...L...--L--.&.--J,......J 

1 10 100 

DISTANCE, IN KILOMETERS 

Figure 4. Comparison of 70 percent prediction 

intervals for peak horizontal acceleration 

recorded at base of small structures for 

magnitude classes 5.0-5.7, 6.0-6.4, 

7.1-7.6. Curves taken from figures 1-3. 

Figure 3. Peak horizontal acceleration versus 

distance to slipped fault for magnitude 

range 7.1-7.6 recorded at base of small 

structures. Symbols and curves same as in 

figure 1. 
0 

z 

0 

u 100.0 UJ 

(./) 

~ 

UJ 

c... 

(./) 

~ 

UJ 

1--

UJ 

~ 

j:: 10.0 

z 

UJ 

u 

z 

>-' 

1--

0 

0 

uj 1.0 

> 

....J 

~ z 

0 

N 

~ 

0 

I 

0.1 1 

EXPLANATION 

X Rock site 

0 Soil site 

10 100 

DISTANCE, IN KILOMETERS 

Figure 5. Peak horizontal velocity versus distance from slipped fault for magnitude 

range 5.3-5.7 recorded at base of small 

structures. Symbo 1 s and curves same as in 

figure 1. 

Figure 7. Peak horizontal velocity versus distance to slipped fault for magnitude range 7.1-7.2 recorded at base of small 

structures. Symbols same as in figure 1. 

8 

0 

z 

0 u 100.0 UJ 

(./) 

~ 

UJ 

c... 

(./) 

~ 

UJ 

1--

UJ 

~ j:: 

z 

UJ 

u 

z 

>-' 

1--

8 

uj 1.0 

> 

10 100 

DISTANCE, IN KILOMETERS 

Figure 6. Peak horizontal velocity versus distance to slipped fault for magnitude 6.4 

recorded at base of sma 11 structures. 

Symbols and curves same as in figure 1. 

0 

z 

0 

u 100.0 UJ 

(./) 

~ 

UJ 

a.. 

(./) 

Q:: 

UJ 

1--

UJ 

~ 

i= 10.0 

z 

UJ 

u 

z 

>-' 

1--

8 

uj 1.0 

> 

....J 

~ z 

0 

N 

Q:: 

0 

I 

10 100 

DISTANCE, IN KILOMETERS 
0 

z 

0 u 100.0 w 

en 

a:: 

w 

a.. 

en 

a:: 

w 

1--

w 

:E 

~ 10.0 

z 

w 

u 

z 

>-' 

1--

8 

....J 

w 

> 

....J 

$ 

z 

0 

N 

a:: 

0 

I 

5.3-5.7 

6.4 7.1-7.2 

' ' ....., 

I ll 1 

-:-..., I 

' I 

'~ I 

I 

I 

DISTANCE, IN KILOMETERS 

Figure 8. Comparison of 70 percent prediction intervals for peak horizontal velocity 

recorded at base of small structures for 

three magnitude classes 5.3-5.7, 6.4, and 

7.1-7 .2. Curves for magnitude classes 

5.3-5.7 and 6.4 taken from figures 5 and 

6. Dashed lines for class 7.1-7.2 

emphasize uncertainty in slope. 

en 

a:: 

w 

1--

w 

:E 

~ 

z 

w 

u 

z 

....: 

z 

w 

:E 

w 

u 

<( 

....J 

a.. 

en 

0 

....J 

~ z 

0 

N 

a:: 

0 

I 

MAGNITUDE 5.3-5.7 SMALL STRUCTURES 

10 100 

DISTANCE, IN KILOMETERS 9 

en 

a:: 

w 

1--

w 

:E 

~ 

z 

w 

u 

z 

.....:-

z 

w 

:E 

w 

u 

<( 

....J 

a.. 

en 1.0 

0 

....J 

~ z 

0 

N 

a:: 

0 

I 

0.1 

1 10 100 

DISTANCE, IN KILOMETERS 

Figure 10. Peak horizontal displacement versus 

distance to slipped fault for magnitude 6.4 

recorded at base of sma 11 structures. 

Symbols and curves same as in figure 1. 

Figure 9. Peak horizontal displacement versus 

distance to slipped fault for magnitude 

range 5.3-5.7 recorded at base of small 

structures. Symbols and curves same as in 

figure 1. 
(f) 

~ 

w 

....... 

w 

~ 

i= 

z <> 

w <> 

u 

z <><> 

....: 

z 

w <> <> 

~ w 

u 

<( 

_, 

a.. 

(f) 1.0 

a 

_, 

$ 

z 

0 

N 

Ci 

0 

:r: 

0. 1 L____J,___;L-..J..__j___!...J....J...L..L..---1---L-.L-L-..............,u.L-:---'-__.___.___. 

1 10 100 

DISTANCE, IN KILOMETERS 

Figure 11. Peak horizontal displacement versus 

distance to slipped fault for magnitude 

range 7. l-7.2 recorded at base of small 

structures. Symbols same as in figure 1. 

Figure 13. Duration versus distance from slip- ped fault for recordings from small 

structures. 

10 

(f) 

~ 

w 

....... 

w 

~ 

i= 

z 

w 

u 

z 

....: 

z 

w 

~ w 

u 

<( 

_, 

6 4 7.1-7.2 . ~ 

N', 

l ' I ', 1 1 I 1 

I l._ I I 

IN~': ', I 

,l 

I 'i 

a.. 1.0 (f) I 

a I _, I 

$ 

z 

0 

N 

~ 

0 

:r: 

0.1 

1 10 100 

DISTANCE, IN KILOMETERS 

Figure 12. Comparison of 70 percent prediction 

intervals for peak horizontal displacement recorded at base of small structures for 

three magnitude classes 5.3-5.7, 6.4, and 

7.1-7.2. Curves for magnitude classes 

5.3-5.7 and 6.4 taken from figures 9 and 

10. Dashed lines for class 7.1-7.2 

emphasize uncertainty in slope. 

SMALL STRUCTURES 40.0 ,.-----___,1:....:.....:.::....:.=--=-..:..:...,.:l=---=-:._::_______:_,-,----, 

X X X~ 

EXPLANATION 

~ Magnitude class 5.3-5.7 

0 Magnitude class 6.4 

30.0 r- 0 - (f) 'il Magnitude class 7.1-7.2 

0 

z x Zero duration (see text) 

0 

u 

w 

(f) 

z 

20.0 r- 0 v - z .. 0 

i= 

<( 0 0 v 

~ 0 v 

5 6. 

10.0 ,_. ():) 0 -

AA 0 

08 0 

6. 

D. 0 D. 

0.0 .t I l I _.......... 

0 25 50 75 100 

DISTANCE, IN KILOMETERS 
0> 

z 

z~ 

0 

i= 

1.0 

<( 0.1 ~ ~ ~ w 

_, 

w 

u 

u 

<( 

EXMN~ X Rock site 

<> Soil site 

X X 

<> 

X<> $1 

<> 

<> 

xoo 

0.00 1 L____J,___j___L....L..I.....LLLJ..._~____.J~~~.J__~-;j--'~ 

1 10 100 

DISTANCE, IN KILOMETERS 

Figure 14. Peak vertical acceleration versus 

0> 

z 

z~ 

0 

i= 

<( 

~ 

w 

_, 

w 

u 

u 

<( 

_, 

<( 

u 

i= 

~ 

w 

> 

distance to slipped fault for magnitude 

range 5.0-5.7 recorded at base of small 

structures. Symbols and curves same as in 

figure 1. 

1.0 

0 

<> 

0.1 

X 

Oo8 

0~~0 0 

0.01 X X 

X ~ 0 

0 /.. 

>---

0.001 

1 

DISTANCE, IN KILOMETERS 

11 

0> 

z 

z 

0 

i= 

<( 

~ 

w 

_, 

w 

u 

u 

< 

6 

i= 

1.0 

0.1 

ffi 0.01 

> 

0.00 1 l,___J___J__L....L..L....LLLJ...____j____.J~-L.J..~:-:-----~-~ 

1 10 

DISTANCE, IN KILOMETERS 

Figure 16. Peak vertical acceleration versus 

distance to slipped fault for magnitude 

range 7.1-7.6 recorded at base of small 

structures. Symbo 1 s and curves same as in 

figure 1. 

Figure 15. Peak vertical acceleration versus 

distance to slipped fault for magnitude 

range 6.0-6.4 recorded at base of sma~l 

structures. Symbols and curves same as 1n 

figure 1. 
0 

5100.0 

u 

w 

(/) 

Q::: 

w 

Cl.. 

(/) 

Q::: 

w 

tw 10.0 ~ 

t= 

z 

w 

u 

z 

>-' 

t0 1.0 0 

__. 

w 

> 

__. 

6 

t= 

Q::: 

w 

> 

0.1 

1 10 100 

DISTANCE, IN KILOMETERS 

Figure 17. Peak vertical velocity versus distance to slipped fault for magnitude range 

5.3-5.7 recorded at base of small 

structures. Symbols and curves same as in 

figure 1. 

Figure 19. Peak vertical velocity versus distance to slipped fault for magnitude range 

7.1-7.2 recorded at base of small 

structures. Symbols same as in figure 1. 

12 

0 

z 0100.0 

u 

w 

(/) 

Q::: 

w 

Cl.. 

(/) 

Q::: 

w 

tw 

~ 10.0 

t= 

z 

w 

u 

z 

>-' 

t0 

0 1.0 __. 

w 

> 

__. 

6 

t= 

Q::: 

w 

> 

0.11 10 100 

DISTANCE, IN KILOMETERS 

Figure 18. Peak vertical velocity versus distance to slipped fault for magnitude 6.4 

recorded at base of sma 11 structures. 

Symbols and curves same as in figure 1. 

0 

z 

0100.0 

u 

w 

(/) 

~ 

w 

Cl.. 

(/) 

~ 

w 

tw 

~ 10.0 

t= 

z 

w 

u 

z 

>-' 

t0 

0 1.0 __. 

w 

> 

__. 

6 

t= 

Q::: 

w 

> 

0.1 

MAGNITUDE 7.1-7.2 SMALL STRUCTURES 

1 10 100 

DISTANCE, IN KILOMETERS 
MAGNITUDE 5.3-5.7 SMALL STRUCTURES 

(/) 

0! 

w 

1--

w 

~ 

i= 

z 

w 

u 

z 

....: 

z 

w 

~ w 

u 

<( 

-1 1.0 0... 

(/) 

0 

-1 

6 

i= 

0! 

w 

> 

DISTANCE, IN KILOMETERS 

Figure 20. Peak vertical displacement versus 

distance to slipped fault for magnitude 

range 5.3-5.7 recorded at base of small 

structures. Symbols and curves same as in 

figure 1. 

MAGNITUDE 6.4 SMALL STRUCTURES 

(/) 

0::: 

w 

1--

w 

~ 

i= 

z 

w 

u 

z 

.....:-

z 

w 

~ w 

u 

<( 

-1 1.0 0... 

(/) 

0 

-1 

<( X 

u 

i= 

0! 

w 

> 

0.1 

1 10 100 

DISTANCE, IN KILOMETERS 

13 

(/) 

0! 

w 

1--

w 

~ 

i= 

z 

w 

u 

z 

...,: 

z 

w 

~ w 

u 

<( 1.0 -1 

0... 

(/) 

0 

-1 

6 

i= 

0! 

w 

> 

0.1 

1 10 

DISTANCE, IN KILOMETERS 

Figure 22. Peak vertical displacement versus 

distance to slipped fault for magnitude 

range 7.1-7.2 recorded at base of small 

structures. Symbols same as in figure 1. 

Figure 21. Peak vertical displacement versus 

distance to slipped fault for magnitude 6.4 

recorded at base of sma 11 structures. 

Symbols and curves same as in figure 1. 
0> 

z 

z~ 

0 

i= 

<( 

0::: 

UJ 

....J 

UJ 

u 

u 

<( 

....J 

~ z 

0 

N 

0::: 0 0.01 

I 

0 . 00 1 ._______...___.___.__._._.J...J...J-......_____...___.__.__._._..._.__._......____.-+-IIf---+--J 

1 

DISTANCE, IN KILOMETERS 

Figure 23. Peak horizontal acceleration versus 

distance to slipped fault for magnitude 

range 5.0-5.7 including data from both 

large and small structures. The center 

line is the mean regression line. The 

outer pair of lines. represents the 95 

percent prediction interval, and the inner 

pair represents the 70 percent prediction interval. Length of lines represents the 

distance interval considered in the 

regression analysis. 

Figure 25. Peak horizontal acceleration versus 

distance to slipped fault for ~agnitude 

range 7.1-7.6 including data from both 

large and small structures. Symbols and 

curves Sime as in Figure 23. 

14 

O'l 

z 

z~ 

0 

i= 

<( 

0::: 

UJ 

....J 

UJ 

u 

u 

<( 

....J 

~ z 

0 

N 

0.1 

0::: 0.01 

0 

I 

+ 

0 

0 

+-¢1-tB 

1 

+ 

-HEIIJ 

IDl 

DISTANCE, IN KILOMETERS 

Figure 24. Peak horizontal acceleration versus 

distance to slipped fault for magnitude 

range 6.0-6.4 including data from both 

large and small structures. Symbols and 

curves same as in Figure 23. 

0> 

z 

z~ 

0 

i= 

<( 

Cll:: 

UJ 

1.0 

....J 0.1 UJ 

u 

u 

<( 

....J 

~ 

5 

N 

~ 0.01 

10 100 

DISTANCE, IN KILOMETERS 
0 

z 

8 100.0 w 

(/) 

~ 

w 

0... 

(/) 

~ 

w 

1-

w 

:E i= 10.0 

z 

w 

u 

z 

>-' 

1-

8 uj 1.0 

> 

EXPLANATION 

+ Rock site 

D Soil site 

0 0 

0 

+ 

DISTANCE, IN KILOMETERS 

Figure 26. Peak horizontal velocity versus 

distance to slipped fault for magnitude 

range 5.3-5.7 including data from both 

large and small structures. Symbols and 

curves same as in figure 23. 

0 

z 

8100.0 

w 

(/) 

~ 

w 

0... 

(/) 

~ 

w 

1-

w 

:E i= 10.0 

z 

w 

u 

z 

>-' 

I0 

0 

....J 

w 

> 

....J 

<( 

Iz 

0 

N 

~ 

0 

I 0.1 

MAGNITUDE 6.4 ALL STRUCTURES 

1 10 

DISTANCE, IN KILOMETERS 

15 

MAGNITUDE 7. 1 

0 

z 

8100.0 

w 

(/) 

~ 

w 

0... 

(/) 

~ 

w 

1-

w 

:E i= 10.0 

z 

w 

u 

z 

>-' 

1-

0 

0 

....J 1.0 w 

> 

100 

DISTANCE, IN KILOMETERS 

Figure 28. Peak horizontal velocity versus 

distance to slipped fault for magnitude 

range 7.1-7.2 including data from both 

1 arge and sma 11 structures. Symbo 1 s same 

as in figure 23. 

Figure 27. Peak horizontal velocity versus 

distance to slipped fault for magnitude 6.4 

including data from both large and small 

structures. Symbols and curves same as in 

figure 23. 
(/) 

0:::: 

UJ 

1-

UJ 

::?! 

i= 

z 

UJ 

u 

z 

t-=' 

z 

UJ 

::?! 

UJ 

u 

<( 

.....J 

a... 

(/) 

0 

.....J 

<( 

1-

z 

0 

N 

0:::: 

0 

I 

10.0 

1.0 

0.1 

1 

EXPLANATION 

+ Rock site 

o Soil site 

10 100 

DISTANCE, IN KILOMETERS 

Figure 29. Peak horizontal displacement versus 

distance to slipped fault for magnitude 

range 5.3-5.7 including data from both 

large and small structures. Symbols and 

curves same as in figure 23. 

Figure 31. Peak horizontal displacement versus 

distance to slipped fault for magnitude 

range 7.1-7.2 including data from both 

1 arge and sma 11 structures. Symbo 1 s same 

as in Figure 23. 

16 

(/) 

0:::: 

UJ 

1-

UJ 

::?! 

i= z 10.0 

UJ 

u 

z 

t-=' 

z 

UJ 

::?! 

UJ 

u 

<( 

.....J 

a... 

(/) 

{5 

.....J 

~ z 

0 

N 

0:::: 

0 

I 

1.0 

MAGNITUDE 6.4 ALL STRUCTURES 

DISTANCE, IN KILOMETERS 

Figure 30. Peak horizontal displacement versus 

distance to slipped fault for magnitude 6.4 

including data from both large and small 

structures. Symbols and curves same as in 

figure 23. 

MAGNITUDE 7.1 - 7.2 ALL STRUCTURES 

(./) 

0:::: 

UJ 

1-

UJ 

::?! 

i= 

z 10.0 

UJ 

u 

z 

t-=' 

z 

UJ 

~ UJ 

u 

<( 

.....J 

a... 

(/) 1.0 

{5 

.....J 

~ z 

0 

~ 

0:::: 

0 

I 

10 100 

DISTANCE, IN KILOMETERS 
SAN FERNANDO EARTHQUAKE 

The San Fernando earthquake supplied more 

than one-quarter of the total data points in 

our samp 1 e. The 1 arge number of data points 

from a single event provides the best basis 

for examining the effect of structure and 

local site conditions. The San Fernando 

earthquake also gives more accurate values 

than the whole magnitude 6.0-6.4 data set for 

the slopes of the regression lines for peak 

parameters against distance. This accuracy is 

possible because, as mentioned previously, the 

statistical analysis can be carried out over a 

greater range of distance for the San Fernando 

earthquake. As discussed earlier, to avoid 

bias not all the records from downtown Los 

Angeles are included in the data set. 

In comparing peak parameters for different 

structural types and site conditions, we use 

an analysis of variance technique (Acton, 

1959, p. 80-83) to test the statistical 

significance of the observed differences 

between one data set and another. To state 

the matter more precisely, we consider the 

variance of the residuals and examine the 

statistical signficance of the reduction in 

variance that occurs when different regression lines are fit to the two different data sets. 

The technique allows us to break down the 

reduction of variance into a component attributable to separate slopes and a 

component attri butab 1 e to separate means. In 

what follows, when we say a difference is 

significant we mean that it corresponds to a 

significant reduction in the variance of the 

residuals. In general, the analysis of 

variance tests enable us to see how the 

differences between data sets compare with 

those that might be caused by random samp 1 i ng 

error. We shou 1 d not be confident, however, 

that the strong-motion data sets represent random samples, and, in any case, the 

statistical tests say nothing about the real 

physical meaning of the differences between 

data sets. 

Effect of structure. -- Figure 32 compares peak horizontal acceleration values recorded 

on soi 1 at the base of small structures (Sl) 

and large structures (S2). Figure 33 shows 

the mean regress ion 1 i nes and the 70 percent prediction intervals determined separately for 

the Sl and S2 data. The mean regression line 

for the Sl data 1 i es above that for the S2 

data, and the analysis of variance tests 

indicate that the difference is significant at 

the 90 percent level. The difference in slope 

is not significant. The same comparisons are 

made for horizontal velocity in figures 34 and 

35. For velocity, the mean regression line 

for the Sl data 1 i es generally be 1 ow that for 

the S2 data, although they cross, and the 

difference is statistically significant at the 

98 percent level, though unimpressive to the 

eye. The Sl line is steeper, and the 

17 

difference in slope is significant at the 90 

percent level. The horizontal displacement data (fig. 36 and 37) show that the mean 

regression line for the Sl data lies below 

that for the S2 data, and the difference is 

significant at the 99 percent level. The 

difference in slope is not significant. 

In summary, for most of the distance range 

covered by the regression analysis peak 

horizontal acceleration is less and peak 

horizontal velocity and displacement are 

greater, on the average, at the base of 1 arge 

structures than at the base of small 

structures. The attenuation with distance is 

greater for the small structures for all three 

parameters, but the difference is statistically significant only for peak velocity. 

The result that acceleration values from the 

1 arge structures are lower on the average is 

what would be expected if soil-structure 

interaction biases those data downward. This 

result encourages us in our preference for the 

data from small structures as a basis for 

estimating free-field ground motion. In 

general, however, the differences between the 

data from the 1 arge structures and the sma 11 

structures are relatively small compared with 

the range of either data set, and we do not 

believe that firm conclusions are warranted 

solely on the basis of formal statistical 

tests. The differences may be due to 

soil-structure interaction, but more study would be required to demonstrate this. 

Effect of site geology. -- Figure 38 compares peak horizontal acceleration recorded at the 

base of sma 11 structures on rock and soi 1. 

Figure 39 shows the mean regression line and 

70 percent confidence intervals determined 

separately for the two data sets. The 

analysis-of-variance tests indicate that the 

differences are not significant in either 

slope or level. Peak horizontal velocity data 

for small structures on both rock and soil 

sites (figs. 40 and 41) show that the mean 

regression line is higher for soil, and that 

difference is significant at the 98 percent level. The difference in slope is not 

significant. Peak horizontal displacement 

data (figs. 42 and 43) show that the mean 

regression line for soil is higher, and that 

difference is significant at the 98% level. 

The difference in slope is not significant 

even at the 75 percent level. 

Apparently, peak horizontal acceleration 

is nearly the same, on the average, on rock 

and soil sites, whereas both peak horizontal 

velocity and displacement are larger on soil 

sites. This relation is not the result of any 

obvious bias in the data. No gross effect is 

evident from bias in the distribution of 

stations with distance. To test for bias due 

to the nonuniform azimuthal distribution of 

the data (Hanks, 1975), we determined the 

azimuth of each station with respect to a 

point in the center of the zone of fault 
rupture (lat 34.370 N., long 118.420 w.). A mean regression line against distance was 

determined for all the peak horizontal 

acce 1 erati on data for sma 11 structures in the 

distance range 15-100 km (with distance 

measured to the closest point on the rupture 

surface, as before). Residuals to that 

regression line are plotted against azimuth in 

a polar diagram (fig. 44). The circle 

represents zero residual. No strong systematic difference is apparent between rock 

and soil. Figure 45 gives the corresponding plot for the velocity data. Although the 

azimuthal coverage is far from complete, we 

can say that in any range of azimuth for which 

both rock and soil points are present, the 

soil residuals are more positive. Similar 

results are obtained for the displacement data 

(fig. 46). 

1.0 

0> 

z 

z' * lw 0 

<( 

~ * ~<> 

~ 0.1 * ~*<> w 

* __. 

w 

u 

: il<><> u 

<( 

__. 

<( 

1--

z 

0 

N 0.01 ~ EXPLANATION 

0 0 Small structure I * Large stucture 

o .oo 1 L1 _ _L_L..LLU...w1 o _ ____l_L.J._..LJLLL:L:-:--....J.._~--L-J 

DISTANCE, IN KILOMETERS 

Figure 32. Peak horizontal acceleration versus 

distance to s 1 i pped f au 1 t at so i 1 sites in 

San Fernando earthquake. 

18 

We tentatively cone 1 ude that amp 1 i fi cation 

of velocity and displacement is a real effect 

associated with soi 1 sites. We presume that 

for the soil sites some sort of amplification 

mechanisms are operating on the longer periods that are dominant on velocity and displacement records. For the shorter periods that are 

dominant on acceleration records, these 

mechanisms are counterbalanced by anelastic 

attenuation. We will not speculate here on 

the nature of the amplification mechanisms. 

Similar conclusions on the effect of site 

conditions on strong motion in the San 

Fernando earthquake were reported by Duke, 

Johnsen, Larson, and Engman (1972), Trifunac 

(1976), and Arnold, Vanmarcke, and Gazetas 

(1976). 

1.0 

0> 

z 

z' 

0 

~ 

<( 

~ 

w 

___. 0.1 w 

u 

u 

<( 

___. 

<( 

1--

z 

0 

N 

~ 0.01 0 EXPLANATION 

I --Small structures 

--Large structures 

0.0011 10 

DISTANCE, IN KILOMETERS 

Figure 33. Comparison of mean regression lines 

and 70 percent prediction intervals for small 

structures (solid lines) and large structures 

(dashed lines) for peak horizontal 

acceleration at soil sites in San Fernando 

earthquake. 
SAN FERNANDO SOIL SITES 

Q 

z 

0 u 100.0 

w 

(./) 

0::: 

w 

Q.. 

(./) 

0::: **~ 

=~ w 

~ 

w 

~ 

i= 10.0 

z 

w ~ u <>~ <> 

z 

<0\> * <>o >-' 

~ 

0 

0 

-.I 1.0 w EXPLANATION 

> 0 Sma II structure -.I 

~ * Large structure 

z 

0 

N 

0::: 

0 

I 0.1 

1 10 100 

DISTANCE, IN KILOMETERS 

Figure 34. Peak horizontal velocity versus 

tance to s 1 i pped fault at soil sites in 

Fernando earthquake. Symbols same as 

figure 32. 

Q 

z 

8100.0 

w 

(./) 

0::: 

w 

Q.. 

(./) 

0::: 

w 

~ 

w 

~ i= 10.0 

z 

w 

u 

z 

>-' 

~ 

8 

-.I 1.0 w 

> 

....J 

~ z 

0 

N 

0::: 

0 

I 

SAN FERNANDO SOIL SITES 

EXPLANATION 

-Small structures 

- -Large structures 

10 100 

DISTANCE, IN KILOMETERS 

disSan 

in 

19 

(./) 

0::: 

w 

~ 

w 

~ 

i= 

z 

w 

u 

z 

....: 

z 

w 

~ w 

u 

<( 

-.I 

Q.. 

(./) 

i5 

-.I 

~ z 

0 

N 

02 

0 

I 

10.0 

1.0 

SAN FERNANDO SOIL SITES 

EXPLANATION 

0 Small structure * Large structure 

0 ·

1 1 10 100 

DISTANCE, IN KILOMETERS 

Figure 36. Peak horizontal displacement versus 

distance to slipped fault at soil sites in 

San Fernando earthquake. Symbols same as in 

figure 32. 

Figure 35. Comparison of mean regression lines 

and 70 percent prediction intervals for small 

structures (solid lines) and large structures 

(dashed lines) for peak horizontal velocity 

at soil sites in San Fernando earthquake. 
(f) 

~ 

w 

1-

w 

:E 

i= 

SAN FERNANDO SOIL SITES 

0> 

z 

z 

0 

i= 

<( 

~ 

w 

.....J 

w 

u 

u 

<( 

1.0 

0.1 

~ 10.0 

u 

.....J 

~ z 

0 

N z 

....: 

z 

w 

:E 

w 

u 

<( 

.....J 

a.. 

(f) 

0 

.....J 

~ z 

0 

N 

~ 

0 

I 

1.0 

EXPLANATION 

- Small structures 

- - Large structures 

10 100 

DISTANCE, IN KILOMETERS 

~ 0.01 

0 

I 

EXPLANATION 

X Rock site 

OSoil site 

0 .00 1 L------1-L-.L_j_JJ...LLL--...I.....-...J.._L...J......L...WI....LI---l---1--l-J 

1 10 100 

DISTANCE, IN KILOMETERS 

Figure 38. Peak horizontal acceleration recorded 

at base of small structures versus distance 

to slipped fault in San Fernando earthquake. 

Symbols same as in figure 1. 

1.0 Figure 37. Comparison of mean regression lines 0> 

and 70 percent prediction intervals for small z 

structures (solid lines) and large structures 

(dashed lines) for peak horizontal z 

displacement at soil sites in San Fernando 0 

earthquake. ~ 

Figure 39. Comparison of mean regression lines 

and 70 percent prediction intervals for rock 

sites (solid lines) and soil sites (dashed 

lines) for peak horizontal acceleration 

recorded at base of sma 11 structures in San 

Fernando earthquake. 

20 

~ 

w 

uj 0.1 

u 

u 

<( 

.....J 

~ z 

0 

N 

~ 0 0.01 

I 

EXPLANATION 

- Rock sites 

-- Soil sites 

10 100 

DISTANCE, IN KILOMETERS 
0 

z 

0 u 100.0 w 

(/) 

0::: 

w 

c.. 

(/) 

0::: 

w 

1-

w 

~ 

i= 10.0 

z 

w 

u 

z 

~ 1-

0 

0 

u:: 1.0 

> 

....... 

~ z 

0 

N 

0::: 

0 

I 

EXPLANATION 

X Rock site 

0 Soil site 

X 

10 100 

DISTANCE, IN KILOMETERS 

Figure 40. Peak horizontal velocity recorded 

0 

z 

at base of small structures versus distance 

to slipped fault in San Fernando 

earthquake. Symbols same as in figure 1. 

8100.0 

w 

(/) 

0::: 

w 

c.. 

(/) 

0::: 

w 

1-

w 

~ i= 10.0 

z 

w 

u 

z 

>-' 

1-

8 

....... 1.0 w 

> 

....... 

~ z 

0 

N 

0::: 

EXPLANATION 

--Rock sites 

---Soil sites 

0 

I 0 . 1 L....----L----l--L....J......J...~.L......----L--1--J.......L...L..J....LL...___-----L----J'--'--I 

1 10 100 

DISTANCE, IN KILOMETERS 

21 

(/) 

0::: 

w 

1-

w 

~ 0 i= 

z 10.0 w xx 0 u ><> 

z 

X 0 

.....: 

z oo 0 w 

~ X oo 

u 

w 0~ X 0 <( 

....... 

c.. xo 0 (/) 1.0 0 EXPLANATION ~ ....... X Rock site 

~ 0 Soil site z 

0 

N 

0::: 

0 

I 

0.1 

1 10 100 

DISTANCE, IN KILOMETERS 

Figure 42. Peak horizontal displacement recorded at base of sma 11 structures versus 

distance to slipped fault in San Fernando 

earthquake. Symbols same as in figure 1. 

Figure 41. Comparison of mean regression lines 

and 7p percent prediction intervals for 

rock sites (solid lines) and soil sites 

(dashed lines) for peak horizontal velocity 

recorded at base of sma 11 structures in San 

Fernando earthquake. 
(/) 

~ 

UJ 

1--

UJ 

~ 

i= 

z 

UJ 

u 

z 

....:-

z 

UJ 

~ UJ 

u 

~ ---' c.. 

(/) 

c 

---' 

~ 1--

z 

0 

N 

~ 

0 

I 

0.1 

1 

EXPLANATION 

Rock site 

-- Soil site 

10 

\ 

\ 

\ 

\ 

' ' ' ' ' 

100 

DISTANCE, IN KILOMETERS 

Figure 43. Comparison of mean regression lines 

and 70 percent prediction intervals for 

rock sites (solid lines) and soil sites 

(dashed 1 i nes) for peak horizonta 1 

displacement recorded at base of small 

structures in San Fernando earthquake. 

Figure 45. Peak horizontal velocity recorded 

at base of sma 11 structures, San Fernando 

earthquake. Azimuthal dependence of 

residuals from mean regression line. 

Symbols same as in figure 44. 

22 

SAN FERNANDO 

SMALL STRUCTURES 

~ 

ACCELERATION 

A FACTOR OF TWO 

Figure 44. Peak horizontal acceleration recorded at base of small structures, San 

Fernando earthquake. Azimuthal dependence of residuals from mean regression line. 

X • s and diamonds are rock and soil sites, 

respectively. 

SAN FERNANDO 

SMALL STRUCTURES 

~ 

<> 

<> 

A FACTOR OF TWO 

VELOCITY 
SAN FERNANDO 

51\f\All STRUCTURES 

<> 

<> 

<> L______j <> 

A FACTOR OF TWO 

DISPLACEMENT 

Figure 46. Peak horizontal displacement recorded at base of small structures, San 

Fernando earthquake. Azimuthal dependence 

of residuals from mean regression line. 

Symbols same as in figure 44. 

PREVIOUSLY PUBLISHED CURVES 

FOR PEAK ACCELERATION 

There are a number of pub 1 i shed 

correlations between ground motion parameters 

and distance, magnitude and site conditions. 

They have been described by Trifunac and Brady (1976) and discussed by Seed and others 

( 1976). We consider here only three recently 

published, widely known relations proposed for 

peak acceleration. 

All studies of strong motion data are 

handicapped by the limited number of data 

points at small distances from the source. 

Attempts to predict strong motion parameters 

at short distance are forced to rely upon rather tenuous assumptions. 

Curves for mean peak acceleration are 

shown in figure 47 for a magnitude 6.6 

earthquake. Also shown is the 70 percent 

prediction interval for the data set for 

magnitude class 6.0-6.4 and small structures, 

from this report. Most of the points in that 

23 

data set came from the magnitude 6.4 San 

Fernando earthquake, so the comparison is 

appropriate from the standpoint of magnitude. 

Data from 1 arge structures, however, were not 

excluded in the development of the other 

curves. 

The curve labeled usn was developed by Schnabel and Seed (1973) for rock sites and is 

based on strong motion data extended to 

distances nearer the fault with the help of 

theoretical attenuation curves. Because the 

theoretical curves are based on the 

conservation of radiated energy, however, they 

apply strictly only to quantities related to 

the energy represented by the whole duration 

of the seismic record. Application of the 

curves to peak parameters is an approx im at ion 

of uncertain accuracy. The measure of 

distance used by Schnabel and Seed is the 

shortest distance to the rupture surface, the 

same measure used in this report. 

The curves labeled 11T0 11 and 11 T2 11 are the 

mean curves given by Trifunac ( 1976) for soft 

and hard sites, respectively. These curves 

are based on a data set very simi 1 ar to the 

one used in this report, including data from 

both large and small structures. The distance 

measure used by Trifunac is epicentral 

distance. The curves were fitted to the data 

on the assumption that the distance dependence is that of the function given by Richter 

(1958) for calculating local magnitudes in 

southern California. The accuracy of that 

assumption is difficult to evaluate. 

Furthermore, the distance function given by 

Richter is not very well defined for distances 

between 0 and 20 km, which is the range most 

important for strong-motion predictions. 

The curve labeled non was developed by Donovan ( 1973) for soi 1 sites. It was 

obtained by fitting 678 data points by a 

function of the form 

b 2m -b 

y = b 1 e (R + 25) 3 

where y is peak acceleration, m is 

magnitude, R is hypocentral distance in 

kilometers and b 1, b 2, and b 3 are 

adjustable constants. The arbitrary constant 

25 that is added to the distance is for the 

purpose of reducing the predicted values at 

small distances. The size of the constant has 

a very 1 arge influence on the va 1 ues at sma 11 

distances, but sufficient data points at these 

distances are not available for a meaningful 

determination of the appropriate size. 

Donovan states that the function fits the data 

better when the arbitrary constant is 25 than 

when it is zero, but it is unclear why it 

should be 25 rather than 15, 10, or 5. 

The corresponding curves are compared in 

figure 48 for a magnitude 7.6 earthquake. The 

solid lines show the 70 percent prediction 

interval for the magnitude 7.1-7.6 data set of 

this report. Most of the points in that data 
set came from the magnitude 7. 2 Kern County 

earthquake. The appare11t inconsistency in 

comparing curves for a magnitude 7.6 

earthquake with data from a magnitude 7.2 

event is connected with the various magnitudes 

that can be given one earthquake. At the time 

that the relations shown in figure 48 were 

developed, the only available magnitude for 

the Kern County earthquake was 7. 7, based on 

surface wave data; it was not until 1978 that 

the Richter local magnitude of 7.2 was 

published. It should be noted that the 

MAGNITUDE 6.6 

1.0 

ro __ T2-.~ ~, OJ 

z s---' '-~ ' 

z o .......... ', \ 

0 

<( 

i= ···-.. ~ 0!: 

UJ 

.....1 0.1 UJ ":>."·. 

u \~·· .. u \'- ·· .. <( '\\ ·· ... .....1 

<( 

1- \~\····· ... z \~. ... 0 

N ·~\ 02 0.01 \' 0 

I ·~ ,, 

\~ ~ 

' 

DISTANCE, IN KILOMETERS 

Figure 47. Proposed relations of peak horizontal acceleration to distance from slipped 

fault for magnitude 6.6 earthquake. Curve 

labeled S is given by Schnabel and Seed 

(1973) for rock sites, curve labeled Dis 

given by Donovan (1973) for soil sites, and 

curves 1 abel ed TO and T2 are mean curves 

given by Trifunac ( 1976) for soft and hard 

sites, respectively. Solid lines show 70 

percent prediction interval for data set 

for magnitude class 6.0-6.4 and small 

structures, from this report. 

24 

commonly used magnitudes wi 11 saturate as the 

size of the earthquake increases. A number of 

recent papers have discussed this important 

point; see, e.g., Brune (1970), Geller (1976), 

Kanamori (1977), and Hanks and Kanamori (1978). 

The amount of disagreement shown in 

figures 47 and 48 is not surprising in view of 

the different assumptions, different measures 

of distance, and different data sets used in 

arr1v1ng at the different curves. The 

disagreement is, as might be expected, the 

greatest at short distances. 

MAGNITUDE 7.6 

1.0 

OJ 

z 

z~ 

0 

i= 

<( 

0!: 

UJ 

.....1 0.1 UJ 

u 

u 

<( 

.....1 

<( 

1-

z 

0 

N 

02 0.01 0 ,, I \\ 

\ 

DISTANCE, IN KILOMETERS 

Figure 48. Proposed relations of peak horizontal acceleration to distance from slipped 

fault for magnitude 7.6 earthquake. Curves 

labeled S, D, TO and T2 are from sources 

given in figure 47. Solid lines show 70 

percent prediction interval for data set 

for magnitude class 7.1-7.6 and small 

structures, from this report. 
ESTIMATION OF PEAK PARAMETERS 

AT SHORT DISTANCES 

The regression lines given in a preceding section of this report provide the means for 

estimating peak ground motion parameter~ at 

distances greater than 5 km for magn1tude 

5.0-5. 7 earthquakes, at distances greater than 

15 km for magnitude 6.0-6.4 earthquakes, and 

at distances greater than 40 km for magnitude 

7.1-7.6 earthquakes. Unfortunately, most of 

the damage from earthquakes can be expected to 

occur at shorter distances. Attempts have 

been made as described in the preceding 

section t~ provide curves for estimating at 

shorter' distances. For reasons given in that 

section, we do not have complete confidence in 

those curves. We will not venture our own set 

of curves but will discuss briefly some of the 

considerations bearing on ground-motion estimates near the source. Further 

discussions of these questions in greater 

depth is given by Boore (1974). 

Several studies have used simplified models of the faulting process to set limits 

on the ground motion at the fault surface 

(Hausner, 1965; Ambraseys, 1969; Brune, 1970; 

Ida, 1973). Brune's {1970) near-source model 

assumes that rupture occurs instantaneously 

over the fault plane. The peak particle velocity is proportional to the stress drop 

and equals 100 cm/s for a stress drop of 10 

MPa {100 bars). The peak acceleration is 

infinite if all frequencies are included, but 

if frequencies above 10 Hz are filtered out of 

the acceleration pulse the peak value is 2g • 

This is a useful model for relating ground 

motion to the physics of the rupture process, 

but it does not give firm upper limits. An 

argument can be made for larger motions if one 

takes rupture propagation into account {Ida, 

1973; Andrews, 1976). Furthermore, the peak values of ground motion may represent 

localized high stress drops, as Hanks and 

Johnson (1976) have suggested for peak acceleration. Such localized stress drops 

might easily exceed 100 MPa. 

The peak acceleration at the surface is 

limited by the strength of near-surface 

materials, as has been pointed out by 

Ambraseys (1974). For sites near the source 

underlain by soil material of low strength, 

this factor may control the value of peak acceleration. This consideration may also 

apply to rock sites if the rock is 

sufficiently weathered. Determination of the 

limiting acceleration, however, would require 

reliable measurement of the dynamic, in situ 

strength of the soil at a particular site. In 

the absence of adequate measurements, one must 

presume that the acceleration could be at 

1 east as 1 arge as 0. 5 g , which was recorded on 

a thickness of more than 60 m of 

25 

water-saturated a 11 uv i urn at station 2 in the 

Parkfield earthquake (Shannon and Wilson, Inc. 

and Agbabian Associates, 1976). 

For displacement, it seems unlikely that 

the peak wou 1 d exceed the static dis 1 ocat ion 

amplitude. The latter is known for many 

historical earthquakes and may be estimated as 

a function of magnitude (Bonilla and Buchanan, 

1970). 

The acce lerogram recorded at Pacoima qam during the San Fernando earthquake has maJOr 

significance for estimates of near-source 

ground motion. The instrument is located only 

3 km from the rupture surface at a rock site 

where the topographic relief is s~ver~. The 

peak recorded hori zonta 1 ac~e 1 erat 1 on 1 s 1. 25 

g velocity 113 cm/s, and d1splacement 38 em. 

This is the only accelerogram in the data set 

recorded within 5 km for an earthquake of 

magnitude as large as 6.4, and as ~uch ought 

to have strong influence on est1mates of 

near-source ground motion. The possibili~y of 

topographic amplification needs conslderation. A two-dimensional finite-difference 

study by Boore ( 1973) suggests that the 

acceleration may have been amplified by as 

much as 50 percent but that the ve 1 oc ity and 

displacement were relatively unaffected. 

Given these considerations, it would be 

difficult for us to accept estimates less than 

about 0.8 g, 110 cm/s, and 40 em, 

respectively, for the mean values of peak acceleration, velocity and displacement at 

rock sites within 5 km of fault rupture in a 

magnitude 6. 5 earthquake. We recognize that 

these numbers represent one earthquake with a 

particular focal mechanism and that estimates 

can be expected to change when more data 

become available. We presume that the 

statistical scatter about the mean will be at 

least as great for sites close to the rupture 

as at the greater distances where data are 

avail able. 

The acce lerograph at Pacoima dam was only 

3 km from the nearest point on the rupture surface but the nearest point was not the 

source ' of the peak motions. As noted 

previously the source for the peak velocity 

and for the peak acceleration are different 

points on the rupture surface separated by perhaps as much as 20 km (Hanks, 1974; Bouchon 

and Aki, 1977). 

Above magnitude 6.5 there are essent~ally 

no data for estimating the effect of magn1tude 

on near-fault peak acceleration, velocity and 

displacement, other than the s~atic fault 

offset as a bound on the peak d1 spl acement. 

Conservatism requires the presumption of some 

increase with magnitude. Hanks and John~on 

(1976) presented a set of peak ac~elerat1on 

data at a source distance of approx1mately 10 

km for earthquakes in the magnitude range 

3.2-7.1. The only data point above magnitude 

6. 5 was for the Imperia 1 Va 11 ey earthquake ?f 

1940 which they assign a magnitude of 7.1 1n 
contrast to our value 6.4, so the data set can 

be applied to magnitudes greater than 6.5 only 

as an extrapolation. The data set shows some 

dependence of peak accelerations on magnitude, but Hanks and Johnson argue that the data are ~onsistent with the idea of magnitude- 1ndependent source properties. The data 

P 1 otted as the 1 ogari thm of peak acce 1 erat ion a~ains~ magnitude can be fit by a straight l1ne w1th a slope equivalent to an increase by 

a factor of 1.4 per magnitude unit. This 

should not be used for extrapolation beyond magnitude 6. 5, however, because the data set 

was deliberately chosen to represent 

relatively high values, and thus the slope of 

the line fitting the data may not be the same 

as the slope of the line representing mean 

values or, for that matter, of the line 

representing values for any fixed probability. 

At sites other than rock sites 

accelerations might be less because of the 

limited strength of near-surface materials, 

but, as previously noted, determining how much 

less would require dynamic, in situ 

measurements of soil properties. The 

amp 1 i fi cation of peak ve 1 oc ity at soil sites 

compared to rock sites may not be so great 

close to the fault because of the energy lost 

in nonlinear soil deformation, but numerical 

modeling (Joyner and Chen, 1975) demonstrates 

the possibility of amplification of velocity by as much as 30 percent even under conditions 

of intense deformation. The possibility of 

greater amplification cannot be excluded. 

Amplification of displacement at soil sites 

should be expected close to the fault, as at 

greater distances, if the soil column is 

sufficiently thick. 

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26 

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27 

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moment-magnitude scales, Journal of 

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ground shaking near the causative fault: 

World Conference on Earthquake Engineering, 

3rd, Wellington, New Zealand, Proceedings, 

v. 1, p. III-94-III-109. 

Ida, Yoshiaki, 1973, The maximum acceleration 

of seismic ground motion: Seismological Society of America Bulletin, v. 63, p. 959-968. 

Jennings, C. W., and Strand, R. G., 1959, Geologic map of California, Santa Cruz sheet, 

scale 1:250,000: California Division of 

Mines and Geology. 

Jennings, C. W., and Strand, R. G., 1969, Geologic map of California, Los Angeles sheet, 

scale 1:250,000: California Division of 

Mines and Geology. 

Joyner, W. B., and Chen, A. T. F., 1975, Calculation of nonlinear ground response in 

earthquakes: Seismological Society of 

America Bulletin, v. 65, p. 1315-1336. 

Kanamori, H., 1977, The energy release in great 

earthquakes, Journal of Geophysical Research, v. 82, p. 2981-2987. 

Kanamori, H., and Jennings, P. C., 1978, Determination of local magnitude, ML, from 

strong-motion accelerograms: Seismological Society of America Bulletin, v. 68, p. 471-485. 

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Acce 1 erograph and sei smos cope records from 

Managua, Nicaragua, earthquakes, in 

Managua, Nicaraua earthquake of December 

23, 1972: Earthquake Engineering Research 

Institute Conference, Proceedings, v. 1, p. 

180-205. 

Lahr, K. M., Lahr, J. C. , Lindh, A. G., Bufe, 

C. G., and Lester, F. W., 1976, The August 1975 Oroville earthquakes: Seismological Society of America Bulletin, v. 66, p. 

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Lindh, A. G., and Boore, D. M., 1973, Another 

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strong motion instruments as a seismic 

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America, Earthquake Notes, v. 44, p. 24. 

28 

Maley, R. P., and Cloud, W. K., 1973, Strongmotion accelerograph records, in San 

Fernando, California, earthquake of 

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and Atmospheric Administration, U.S. 

Department of Commerce, p. 325-348. 

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1975, Strong-motion seismograph results 

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and Geology Special Report 124, p. 115-122. 

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1967, The Parkfield, California, 

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Proceedings, v. 2, p. B4-37-B4-50. 

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earthquake of Apri 1 13, 1949: Se i smo l ogi cal 

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Geological Survey Circular 672, 23 p. 

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Survey Professional Paper 941-A, p. A31-A38. 

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29 

Trifunac, M. D.,and Brady, A. G., 1976, Correlations of peak acceleration, velocity, and 

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81 p. 

Valera, J. E., 1973, Soil conditions and local 

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Earthquake Engineering Research- Institute 

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Conference, Proceedings, v. 1, p. 89-96. 
STATISTICAL PARAMETERS 

Linear regression analysis (Dixon 

and ~·1assey, 1957) was employed to dedescribe the distance dependence of the 

peak parameters. Using the symbol y 

for the peak parameter and the symbol x for distance we fit the data by a 

straight line 

V=A+Bu 

where v = log10 y 

and u = log10 x . 

Values for A and Bare given by 

the following equations 

A = L: v - B L: u 

n 

B = nL:uv - L:uL:v 

nL:uz - (L:u) 2 

where the summations are taken over 

all the points in the data set and n 

is the number of points. The scatter 

in the data is measured by s I , the v u standard error of estimate of v for a 

given u. That quantity is obtained 

from the following equations: 

s I = n - l (s 2 - B s 2 ) vu n=2 v u 

'L 1 [ nL:u 2 - s (L:u) 2] u n (n- l) 

s 2 = 1 [nL:v 2 - (L:v J 2 J. v n (n- 1) 

30 

For a given confidence level, 

the prediction interval for a single 

prediction of v given u is 

- 2 (A + Bu) + t I s j· 1 + l + (u - u) - a 2,n-2 v u y; ~J;-2 

where~ is the mean of u values, the confidence 1 eve 1 is ( l -a), and t I a. 2.,n-2 

is the abscissa of the Student's t distribution for a cumulative probability 

of (l - al2) and (n - 2) degrees of 

freedom. The lines describing the prediction intervals are curved because of 

statistical uncertainty in the regression coefficient B. A measure of that 

uncertainty is the standard error of B, 

which is given by 

The following table lists the statistical parameters A_, B., sv!u"' sB and n 

for the data sets discussed in the text. 

The number of the figure displaying the 

data set is also given. 

u 
Data set Fig. No. A B s vlu SB n 

Horizontal acceleration 

M = 5.0-5.7 class 1---------- 1 0.17 -0.93 0.37 0.46 19 

M = 6.0-6.4 class 1---------- 2 .96 -1.23 .20 .32 16 

M = 7.1-7.6 class 1---------- 3 2.65 -2.01 .26 .43 9 

M = 5.0-5.7 all-------------- 23 .05 - .86 .35 .40 24 

M = 6.0-6.4 all-------------- 24 .81 -1.20 .20 . 15 44 

M = 7.1-7.6 all-------------- 25 2.65 -2.00 .21 . 31 14 

San Fernando Rl-------------- 39 1.45 -1.56 .18 .23 10 

San Fernando Sl-------------- 39 1.09 -1.34 .18 .25 12 

San Fernando S2-------------- 33 .90 -1.29 . 15 . 15 18 

Horizontal velocity 

M = 5.3-5.7 class 1---------- 5 2~35 -1.22 .38 . 61 11 

M = 6.4 class 1-------------- 6 1. 93 - .58 .25 .45 14 

M = 7.1-7.2 class 1---------- 7 2.45 - .72 . 16 .42 6 

M = 5.3-5.7 all-------------- 26 2.31 -1.26 .35 .48 16 

M = 6.4 all------------------ 27 2.35 - .85 .20 . 19 35 

San Fernando Rl-------------- 41 3.12 -1.51 .26 .39 9 

San Fernando Sl-------------- 41 3.06 -1.31 . 16 .23 11 

San Fernando S2-------------- 35 2.60 - .96 .08 .08 18 

Horizontal displacement 

M = 5.3-5.7 class 1---------- 9 1.81 -1.15 .36 .59 11 

M = 6.4 class 1-------------- 10 1.48 - . 55 .30 .53 14 

M = 7.1-7.2 class 1---------- 11 2.34 - .86 .22 .56 6 

M = 5.3-5.7 all-------------- 29 1.60 -1.03 .34 .46 16 

M = 6.4 all------------------ 30 l. 91 - .77 .28 .27 35 

San Fernando Rl-------------- 43 2. 72 -1.52 .25 .38 9 

San Fernando Sl-------------- 43 2.07 - .90 .25 .37 11 

San Fernando S2-------------- 37 2.09 - .76 . 19 . 18 18 

Vertical acceleration 

M = 5.0-5.7 class 1---------- 14 - .27 - .77 .29 .36 19 

M = 6.0-6.4 class 1---------- 15 1.36 -1.70 .20 .32 16 

M = 7.1-7.6 class 1---------- 16 l. 55 -1.58 .21 .39 8 

Vertical velocity ~1 = 5.3-5.7 class 1---------- 17 1.62 - .96 .30 .48 11 

~1 = 6.4 class 1-------------- 18 1.86 - .80 .18 .32 14 

Vertical displacement 

M = 5.3-5.7 class 1---------- 20 l. 22 - .93 .29 .47 11 

M = 6.4 class 1-------------- 21 1.15 - .53 . 14 .25 14 

31 
STRONG-MOTION DATA 

Associated with each earthquake is a six-digit number followed by a four-digit 

number. The first two digits of the six-digit 

number denote the year, the second two the 

month, and the third two the day. The first 

two digits of the four-digit number represent 

the hour {Universal Time) and the second two 

the minute. 

Explanation of abbreviations: 

MAG - Earthquake Magnitude. Richter 

(1958) local magnitude if available, 

otherwise surface wave magnitude, 

except for the 1949 Puget Sound and 

1959 Hebgen Lake events, for which 

the type of magnitude was not 

specified in the literature. 

STA # - Station number as given by the U.S. 

Geological Survey (l976b). 

STRUC - Code for associated structure. One 

if data were recorded at the base of 

a one- or two-story building, two if 

data were recorded at the base of a 

larger building or on a dam abutment. 

DIST - Shortest distance in km to the 

surface of fault slippage. 

AC - Accuracy code for distance. A if 

the uncertainty is less than 2 km, B 

if it is between 2 and 5 km, and C 

if it is between 5 and 25 km. 

32 

ACCEL -

VEL -

DISP -

DUR -

SRC -

GEO -

REF -

* -

Peak acceleration as a fraction of 

the acceleration of gravity. 

Peak velocity in centimeters per 

second. 

Peak displacement in centimeters. 

Duration in seconds, defined as the 

time interval between the first and 

last horizontal acceleration peaks 

equal to or greater than 0.05 g. 

Code denoting source motion data. List 

following the data. 

of strong 

is given 

Code for geologic conditions at 

recording site. S for soil 

(thicker than 4 to 5 meters) and R 

for rock. 

Code for source of information on 

stations. List of references 

follows station list. 

Denotes station selected from the 

special area in downtown los 

Angeles as described in the text. 
LISTING OF STRONG MOTION DATA 

720224 1556 BEAR VALLEY, CALIFORNIA MAG • 5,0 

SOIL STATIONSI ******** HORIZONTAL ******** ****** VERTICAL ****** 

STAff STRUC DIST AC ACCEL VEL DISP OUR SRC ACCEL VEL DISP SRC STATION LOCATtON 

1028 1 31,0 A 0,030 8 0,010 B HOLLISTER • CITY HALL 

741128 2301 BEAR VALLEY• CALIFORNIA MAG • 5,2 

ROCK STA liONS I ******** HORIZONTAL ******** ****** VERTICAL ****** 

STAff STRUC DIST AC ACCEL VEL OISP OUR SRC ACCEL VEL DISP SRC STATION LOCATION 

1032 1 18.0 A o.ou E 0.013 E SAGO CENTRAL • HARRIS RANCH 

SOIL STATIONSI ******** HORIZONTAL ******** ****** VERTICAL ****** 

STAff STRUC DIST AC ACCEL VEL DISP OUR SRC ACCEL VEL OISP SRC STATION LOCATION 

1377 1 8,9 A 0.120 G 0,050 G SAN JUAN BAUTISTA <Cl26) • 24 POLK 

1028 1 10.8 A 0.170 G 0,070 G HOLLISTER • CITY HALL 

1250 1 10,8 A 0,140 G 0.030 G GILROY (C6) • GEOL BLDG• GAL COL 

1202 1 37,0 A 0,030 r, 0.050 G STONE CANYON EASTt CALIF, 

750607 846 FERNDALE, CALIFORNIA MAG = 5,2 

(.) 

(.) ROCK STATIONS: ******** HORIZONTAL ******** ****** VERTICAL ****** 

STAff SHWC DIST AC ACCEL VEL OISP OUR SRC ACCEL VF.:L OTSP SRC STATION LOCATION 

1249 1 32.0 13 0.220 r 0,030 I CAPE MENDOCINO IC5) • PETROLIA 

1278 1 64,0 8 0.100 J SHELTER COVEt STA 2 <C41) • PWR PLT 

SOIL STATIONS: ******** HORIZONTAL ******** oooooo VERTICAL *0 *000 

STAff STRUC OIST AC ACCEL VEL DISP OUR SRC ACCt:.L VEL DISP SRC STATION LOCATION 

1023 1 24.0 B 0,240 T 0.050 I FERNDALE • OLD CITY HALL• RROWN ST 

1398 1 34.0 8 0.190 I 0,030 I PETROLIA (Cl56) • GENERAL STORE 

570322 1944 DALY ClTYt CALIFORNIA MAu = 5,3 

ROCK STATIONS: ****~*** HORIZONTAL ******** •••••• VERTICAL ***000 

STAff STRUC OIST AC ACCEL VEL OISP OUR SRC ACCEL VF.L OISP SRC STATION LOCATION 

1117 1 8,o B 0.127 4,9 2.3 1.6 A 0,051 1.2 o.7 A SAN FRANCISCO • GOLDEN GATE PARK 

SOIL STA liONS I oooooooo HORIZONTAL ******** ****** VERTICAL ****** 

STA• STRUC OIST AC ACCEL VEL DISP OUR SRC ACCEL VEL OISP SRC STATION LOCATION 

1080 2 12.0 B 0.103 5.0 1.1 1.4 A 0,050 2,3 0.6 A SAN FRANCISCO • STATE BLDG 

1065 2 14.0 B 0,055 2.9 le3 o.o A o.036 1. 3 0.4 A SAN FRANCISCO • ALEXANDER BLOG 

1078 2 14.0 B 0,048 s.o 1.4 o.o A 0,034 1.5 o.9 A SAN FRANCISCO • SOUTHERN PACIFIC BG 

1049 2 24.0 B 0.047 1.9 1.5 o.o A 0,023 0,9 1· 3 A OAKLAND • CITY HALL 

1081 2 58,o B 0,007 R o.oos B SAN JOSE • BANK OF AMERICA BLDG 
700912 1430 LYTLE CREEK• CALirORNIA MAG • 5.4 

ROCK ST A liONS I ******** HORIZONTAL ******** ****** VERTICAL ****** 

STA# STRUC OIST AC ACCEL VEL OISP OUR SRC ACCEL VF.:L OISP SRC STATION LOCATION 

290 1 15.0 B 0.205 9.6 2.2 2.8 A o.076 3.2 1.4 A WRIGHTWOOD • 6074 PARK DRIVE 

111 1 18.0 B 0.086 5.5 2.4 1. 1 A 0.093 2.6 1.2 A CEDAR SPRINGS - ALLEN RANCH 

116 1 19.0 B 0.179 A 0.094 A DEVILS CANYO~ • fiLTER PLANT 

278 2 32.0 8 o.o22 A 0.018 A SAN OI~AS • PUDDINGSTONE RESERVOIR 

104 2 46.0 8 0.054 A 0.016 A ARCADIA • SANTA ANITA RESERVOIR 

266 1 5B.o B 0.015 A 0.010 B PASADENA • CIT SEISMOLOGY LAB 

137 2 70.0 8 0.015 A 0.006 A *LOS ANGELES • WATER ~ POWER 

110 1 11 o.o B 0.025 A o.o11 A CASTAIC • OLD RIDGE ROUTE 

SOIL STATIONS& ******** HORIZONTAL ******** ****** VERTICAL ****** 

STA# STRUC DIST AC ACCEL VEL OISP OUR SRC ACCEL VF.L DISP SRC STATION LOCATION 

112 1 18.0 8 0.073 4.0 1.2 0.4 A 0.044 1.3 0.4 A CEDAR SPRINGS • PUMP PLANT 

274 2 28.0 tj 0.119 4.8 1.8 1.0 A 0.055 1. 8 1.5 A SAN AERNARDI~O • HALL or RECORDS 

113 1 29.0 8 0.045 2.5 0.9 o.o A o.042 1.3 o.1 A COLTON • s. CAL. EDISON CO. 

129 2 34.0 8 0.019 A o.oo9 9 LOMA LINDA • UNIV. MED. CENTER 

264 2 57.0 B 0.023 1.5 1.8 o.o A o.015 o.7 0.5 A PASADENA • CIT MILLIKAN LIRRARY 

267 2 60.0 8 0.025 2.0 2.4 o.o A 0.017 1.9 1.4 A PASADENA • CIT JPL LAB 

181 2 66.0 B o.026 A 0.012 A LOS ANGELES • 1640 SOUTH MARENGO 

133 2 77.0 8 0.015 A 0.006 A *HOLLYWOOD STORAGE - BASEMENT 

135 1 71.0 8 0.021 A 0.007 A *HOLLYWOOD STORAGE • P.E. LOT 

125 1 95.0 8 0.010 A 0.006 A LAKE HUGHES ARRAY 1 • fiRE STATION (.) 103 1 113.0 8 0.020 R o.005 8 ANZA • A~ZA POST OfriCE .1::1. 

660628 42b PARKfiELD• CALIFORNIA MAG = 5.5 

ROCK STATIONS: ******** HORIZONTAL ******** ****** VERTICAL ****** 

STA# STRUC OIST AC ACCEL VEL t1ISP OUR SRC ACCEL VEL OISP SRC STATTON LOCATION 

1438 1 16.1 A 0.411 22.S s.s 3.7 A 0.165 4.4 ].4 A CHOLAME•SHANOONt TEMBLOR 

1083 1 63.6 A 0.018 1. 1 1.2 o.o A 0.007 1. 3 0.9 A SAN LUIS OBISPO • CITY REC. RLOG 

110 1 204.0 A o.oo4 A CASTAIC - OLO RJOGE ROUTE 

SOIL STATIONS: ******** HORIZONTAL ******** ****** VERTICAL ****** 

STA# STRUC DIST AC ACCEL VEL OISP OUR SRC ACCEL VEL DISP SRC STATION LOCATION 

1013 1 6.6 A o.so9 78.1 26.4 12.1 A 0.349 14.1 4.3 A CHOLAME•SHANOON ARRAY NO. 2 

1014 1 9.3 A 0.467 25.4 7.1 7.9 A 0.181 7.3 3.4 A CHOLAME•SHANDON ARRAY NO. 5 

1015 1 13.0 A 0.279 u.e 4.4 7.8 A 0.138 4.5 2.1 A CHOLA~E·SHANOON ARRAY NO. 8 

1016 1 17.3 A 0.072 a.o 5.7 0.6 A o.061 s.o 2.6 A CHOLAME•SHANOON ARRAY NOe 12 

1095 1 105.0 A 0.012 2.2 2.5 o.o A 0.007 1.1 1.5 A TArT • LINCOLN HS TUNNEL 

1011 1 112.0 A 0.006 A BUENA VISTA • GROUND STATION 

1028 1 123.0 A o.oo3 R HOLLISTER • CITY HALL 

283 1 162.0 A o.oo4 A 0.002 B SANTA BARBARl • COURTHOUSE 

272 1 208.0 A o.oos A 0.001 B PORT HUENEME • NAVY LABORATORY 

133 2 261.0 A o.oo1 R •HOLLYWOOD STORAGE • BASEMENT 

135 1 261.0 A 0.001 A •HOLLYWOOD STORAGE • P.E. LOT 

475 1 272.0 A 0.001 A PASADENA • CIT ATHENAEU~ 
670621 1804 fAIRBANKS• ALASKA MAG = 5,6 

ROCK STATIONSI ******** HORIZONTAL ******** ****** VERTICAL ****** STA• STRUC OIST AC ACCEL VEL OISP OUR SRC ACCEL VEL OISP SRC STATION LOCATION 

2707 1 15.0 8 0,060 c 0,060 c fAIRBANKS• ALASKA • UNIV Or ALASKA 

691002 456 SANTA ROSAt CALIFORNIA MAG • 5,6 

ROCK STATIONSI ******** HORIZONTAL ******** ****** VERTICAL ****** 

STA• STRUC OIST AC ACCEL VEL DISP OUR SRC ACCI:.L VEL OISP SRC STATION LOCATION 

1057 1 71.0 B 0,007 A o.ooz B PLfASANT HILL • DIABLO VALLEY COL. 

1074 2 79,0 B 0,011 A 0,004 8 SAN rRANCISCO • 390 MAIN 

SOIL STATIONSI ******** HORIZONTAL ******** ****** VERTICAL ****** STA_, ST~UC OIST AC ACCEL VEL DISP OUR SRC ACCEL VF.:L OISP SRC STATION LOCATION 

1093 1 62,0 B o.oos A 0,001 8 SAN PABLO • CONTRA COSTA COLLEGE 

1065 2 79,0 B o.oo8 A 0.003 8 SAN rRANCISCO • ALEXANDER BLDG 

1071 2 79,0 B 0,015 A 0.007 8 SAN rRANCISCO • BETHLEHEM PAC BLDG 

Co) 1078 2 79,0 B o.tH6 A 0,007 El SAN rRANCISCO • SOUTHE~N PACiric BG 01 1049 2 82,0 8 0,006 A 0,002 8 OAKLAND • CITY HALL 

1001 1 109,0 B 0.018 A 0.002 8 APEfL ARRAY • STATION 1 

1002 1 11 o.o B 0.017 A 0,002 8 APffL ARRAY • STATION 2 

691002 619 SANTA ROSAt CALirORNIA MAG = 5,7 

ROCK STATIONSI ******** HORIZONTAL ******** ****** VERTICAL ****** STA_, STRUC OIST AC ACCEL VF.L OISP OUR SRC ACCEL VEL OISP SRC STATION LOCATION 

1057 1 71,0 8 0.009 A 0,002 B PLFASANT HILL • DIABLO VALLEY COL, 1074 2 79,0 8 0.012 B 0,004 B SAN rRANCISCO • 390 MAIN 

SOIL STATIONSI ******** HORIZONTAL ******** ****** VERTICAL ****** STA_, STRUC OIST AC ACCEL VEL OISP OUR SRC ACCEL VEL OISP s~c STATION LOCATION 

1093 1 62.0 8 0.003 A 0,003 8 SAN PABLO • CONTRA COSTA COLLEGf 

1065 2 79,0 8 0.012 A 0,003 8 SAN rRANCISCO • ALEXANDER BLDG 

1071 2 79,0 B 0,027 A 0,007 8 SAN FRANCISCO • BETHLEHEM PAC BLDG 

1078 2 79,0 B 0,020 A 0,008 B SAN FRANCISCO • SOUTHERN PACIFIC BG 

1049 2 82,0 8 0.013 A 0.004 8 OAKLANO • CITY HALL 

1001 1 109,0 B 0.029 A 0,002 8 APEEL ARRAY • STATION 1 

1002 1 110.0 8 0.021 A 0,009 B APEEL ARRAY • STATION 2 
750801 2020 OROVILLE, CALIFORNIA MAG : 5,7 

ROCK STATIONS: •••••••• HORIZONTAL ******** ****** VERTICAL •••••• STA# STRUC DIST AC ACCEL VEL DISP OUR SRC ACCEL VEL DISP SRC STATION LOCATION 

1051 1 8,o A 0.110 s.o 1. 6 o.o H 0.120 5.3 2.7 H OROVILLE SEISMOGRAPH STATION 

1293 1 32.0 A 0,040 H 0,030 H PARADISE (C58) • KEWG TRNSMTR ALOG 

SOIL STATIONS: ******** HORIZONTAL •••••••• ****** VERTICAL •••••• STA# STRUC OIST AC ACCEL VEL DISP I')UR SRC ACCEL VEL OISP SRC STATION LOCATION 

1291 1 30,0 A 0,070 H 0,040 H MARYSVILLE (C56) - COOT MAINT BLDG 

1292 1 31.0 A o.o8o H 0,030 H CHICO <C57) • 2334 FAIR STREET 

730221 1445 POINT MUGUt CALIFORNIA MAG = 6,0 

ROCK STATIONS: ******** HORIZONTAL •••••••• •••••• VERTICAL •••••• STAif STRUC DIST AC ACCEL VEL OISP OUR SRC ACCEL VF.:L OISP SRC STATION LOCATION 

655 1 53.0 s 0,031 E 0,014 E JENSEN FILTER PLT • 13100 AAL80At LA 

SOIL STATIONS: •••••••• HORIZONTAL •••••••• •••••• VERTICAL •••••• STA,_ STRUC OIST AC ACCEL VEL OISP OUR SRC ACCEL VEL OISP SRC STATION LOCATION 

(,.) 272 1 24,0 B 0,130 0 0,040 0 PORT HUENEME • NAVY LABORATORY o- 610 2 51.0 8 0,043 E o.016 E LOS ANGELES • 18321 VENTURA 

657 2 51.0 a 0.036 f 0.012 E SANTA MONICA • 201 OCEAN 

118 2 53,0 B 0,042 E 0,016 E LOS ANGELES • 16661 VENTURA 

497 2 53.0 8 0.060 0 0,010 0 LOS ANGELES • 16633 VENTURA 

512 2 54.0 B o.036 f 0,016 E LOS ANGELES • 16255 VENTURA 

259 2 55,0 8 .o. 032 f o.ol3 E LOS ANGELES • 16055 VENTURA 

461 2 55,0 a 0,040 E 0,023 E LOS ANGELES • 15910 VENTURA 

721223 629 MANAGUAt NICARAGUA MAG : 6,2 

SOIL STATIONS: •••••••• HORIZONTAL •••••••• •••••• VERTICAL ****** 

STA• STRUC DIST AC ACCEL VEL OISP OUR SRC ACCEL VF.L OISP SRC STATION LOCATION 

3501 1 5.0 A 0,390 I') 0.330 0 MANAGUAt NIC. - ~SSO REFINERY 

400519 436 IMPERIAL VALLEYt CALIFORNIA MAG = 6,4 

SOIL STATIONS: ******** HORIZONTAL ******** ****** VERTICAL ****** 

STA• STRUC OIST AC ACCEL VEL OISP OUR SRC ACCEL VEL OtSP SRC STATION LOCATION 

117 1 12.0 B 0,359 36.9 }9,A 29.3 A 0.278 10.8 5.6 A EL CENTRO • IRRIGATION SUBSTA. 
6~0409 228 BORREGO MTN,, CALIFORNIA MAG : 6,4 

ROCK STATIONS: ******** HORIZONTAL ******** ****** VERTICAL ****** 

STA• STkUC DIST AC ACCEL VEL DISP DUR SRC ACCEL VEL OISP SRC STATION LOCATION 

270 1 105,0 A 0,018 F' 0,006 F' PERRIS • RESERVOIR 

280 1 122.0 A 0,048 4.2 2,9 o.o A 0,064 3,7 1. 7 A SAN ONOfRE • SCE NUCLEAR PLANT 

116 1 141.0 A 0,011 F' 0.009 f DEVILS CANYON • fiLTER PLANT 

278 2 168,0 A 0.017 F' 0,004 F' SAN DIMAS • PUDniNGSTONE RESERVOIR 

104 2 190.0 A 0,004 F' o.oo1 F' ARCADIA • SANTA ANITA RESERVOIR 

266 1 2oo.o A o.oo1 F' 0,002 f PASADENA • CIT SEISMOLOGY LAB 

136 2 203,0 A o.012 3.1 2.3 o.o A o.oos 1.2 1.0 A *LOS ANGELES • SUBWAY TERMINAL 

190 2 207.0 A 0,007 F' 0,009 F' LOS ANGELES • 2011 ZONAL 

279 2 229,0 A 0.009 F' 0,006 F' SAN fERNANDO • PACOIMA DAM 

121 2 249,0 A o.oo3 F' 0,001 f fAIRMONT STATION • RESERVOIR 

110 1 256.0 A o.ooe f 0,003 F CASTAIC • OLD RIDGE ROUTE 

SOIL STATIONS: ******** HORIZONTAL ******** ****** VERTICAL ****** 

STA# STRUC DIST AC ACCEL VEL niSP OUR SRC ACCEL VEL DISP SRC STAT ION LOCATION 

117 1 45,0 A 0.142 25.8 12·2 3.1 A 0.036 3.4 3.9 A EL CENTRO • IRRIGATION SURSTA, 

277 2 105.0 A 0,032 6.1 4,4 o.o A 0.014 1.9 1.3 A SAN DIEGO • LIGHT L POWER 

113 1 130.0 A 0,031 3.5 4.3 o.o A 0,022 1.8 1. 1 A COLTON • S, CAL. EDISON CO, (..) 

........ 274 2 132.0 A o.018 F 0,003 f SAN BERNARDINO • HALL OF RECORDS 

112 1 147,0 A 0,006 f 0.003 f CEDAR SPRINGS • PUMP PLANT 

281 2 157,0 A 0,013 4,4 3.5 o.o A 0,006 2.2 1.9 A SANTA ANA • ORANGE CO, ENG, BLDG 

130 1 187.0 A o.o1o 3,2 5.0 o.o A 0,006 1.8 1.8 A LONG BEACH • TERMINAL ISLAND 

131 2 187,0 A o.oo5 f 0.003 F' LONG BEACH • UTILITIES ~LOG, 

288 2 196,0 A 0.019 4,7 2.7 o.o A o.oo8 2.4 1.5 A VERNON • CENTRAL MF'G, TERMINAL 

264 2 197.0 A 0,011 2.3 1.8 o.o A 0,007 1.1 o.8 A PASADENA • CIT MILLIKAN LIBRARY 

475 1 197,0 A 0,010 2.5 2.0 o.o A 0,004 1.0 1.1 A PASADENA • CIT ATHENAEUM 

181 2 199.0 A 0,013 F' 0,003 F' LOS ANGELES • 1640 SOUTH MARENGO 

269 1 203.0 A 0.006 f 0.006 F' PEARBLOSSOM • PUMPING PLANT 

267 2 204.0 A o.oo8 1.3 o.A o.o A o.oos 1.0 0.7 A PASADENA • CIT JPL LAB 

122 2 208.0 A 0,023 F' o.o11 F' GLENDALE • 633 E, BROADWAY 

133 2 211,0 A o.o11 f 0,004 f •HOLLYWOOD STORAGE • BASEMENT 

135 1 211.0 A 0.013 3,2 2.1 o.o A o.oos 1 .1 1 .1 A *HOLLYWOOD STORAGE • P,E. LOT 

118 2 227,0 A o.oo8 f 0,001 F' LOS ANGELES • 16661 VENTURA 

241 2 228.0 A o.ou F' 0.006 F' LOS ANGELES • 8244 ORION 

125 1 253.0 A 0,009 f LAKE HUGHES ARRAY 1 • F'IRE STATION 

2005 2 259,0 A 0,003 F' 0,001 F' MOJAVE GENERATING PLANT 

1052 1 281,0 A o.o1J ,. o.o13 f OSO PU~PING PLANT 

272 1 288.0 A o.oo3 F PORT HUENEME • NAVY LABORATORY 

283 1 341.0 A 0,002 f SANTA BARBARA • COURTHOUSE 

1004 1 342,0 A 0,003 ,. 0,001 F RAKERSF'IELO • HARVEY AUDITORIUM 

1095 1 359,0 A 0,002 f TAF"T • LINCOLN HS TUNNEL 
710209 1400 SAN ~ERNANOOt CALIFORNIA MAG : 6,4 

ROCK STATIONS I ******** HORIZONTAL ******** ****** VERTICAL ****** 

STA* STRUC OIST AC ACCEL VEL DISP OUR SRC ACCfL VEL DISP SRC STATION LOCATION 

279 2 3.2 A 1.251 113.2 37.7 13.3 A 0,718 58.3 19.3 A SAN FERNANDO • PACOIMA DAM 

220 2 16.9 A 0.181 15.0 5.4 6.7 A o.oas 5.0 2.4 A LOS ANGELES • 3838 LANKERSHIM 

266 1 18.4 A 0.204 11.6 5.0 6.7 A 0,093 5.9 2.3 A PASADENA • CIT SEISMOLOGY LAB 

141 1 19.4 A 0,188 20.5 7.3 9.6 A 0.138 7,4 3.4 A LOS ANGELES • GRIFFITH OBSERVATORY 

128 1 21.0 A 0,374 14.6 8.9 14.5 A 0,164 4.1 3.3 A LAKE HUGHES ARRAY 12 • CWR SITE 

126 1 24,0 A 0,200 8.6 1.7 5.7 A 0,170 7.1 1.6 A LAKE HUGHES ARRAY 4 • CwR SITE 

127 1 24.0 A 0,147 4.8 2.4 4,6 A 0,089 3.0 2.2 A LAKE HUGHES ARRAY 9 • CwR SITE 

110 1 26,0 A 0,335 27.8 9,5 19.6 A 0.180 6,4 3.5 A CASTAIC • OLD RIDGE ROUTE 

104 2 26.0 A 0.223 6,7 5.9 10.9 A 0.070 4.5 2.5 A ARCADIA • SANTA ANITA RESfRVOIR 

190 2 26.6 A o.083 13.8 }0.3 4.2 A 0,060 7.1 3.8 A LOS ANGELES • 2011 ZONAL 

137 2 27.1 A 0,188 23.4 13.7 6.4 A 0,078 10.3 6.5 A •LOS ANGELES • WATER & POWER 

121 2 30.0 A 0.103 8,4 1.7 1,8 A 0,043 3,4 1.7 A FAIRMONT STATION • RESERVOIR 

278 2 47,0 A 0.078 4,6 2.1 1.7 A 0,039 2.3 1. A A SAN DIMAS • PUDDINGSTONE RESERVOIR 

290 1 59.0 A 0.057 3.8 1.2 0.1 A 0.037 2.0 1·2 A WRIGHTWOOD • 6074 PARK DRIVE 

1096 1 64,0 A 0,028 1.4 o.8 o.o A 0.018 1.0 o.s A FORT TEJON • CWR SITE 

1027 1 66.0 A o.o57 2.8 0.9 o.o A 0.047 2.1 1.2 A EDMONSTON • GROUND STATION (.) 111 1 87.0 A 0.021 A 0.010 A CEDAR SPRINGS • ALLEN RANCH (X) 282 1 120,0 A 0.019 3,7 2.3 o.o A o.o11 1.7 1.4 A GOLETA • UC FLUID MECHANICS LAB 

280 1 121.0 A 0.016 2.~ 2.1 o.o A 0,012 1.5 2.0 A SAN ONOFRE • SCE NUCLEAR PLANT 

SOIL STATIONSI ******** HORIZONTAL ******** ****** VERTICAL ****** 

STA._ STRUC DIST AC ACCEL VEL OISP OUR SRC ACCEL VEL DISP SRC STATION LOCAl ION 

241 2 7,7 A 0.258 30.o 14.9 18.7 A o.11a 31.9 14.6 A LOS ANGELES • 8244 ORION 

458 2 10,7 A 0.118 31.6 }7.6 22.7 A 0.111 18,1 7.0 A L05 ANGELES • 15107 VAN OWEN 

267 2 13.6 A 0.215 13.9 4.9 7.9 A 0.146 5,9 2.6 A PASADENA • CIT JPL LAB 

461 2 14.8 A 0.148 22.3 8,4 19.5 A 0.120 8,o 2.6 A LOS ANGELES • 15910 VENTURA 

466 2 15.0 A 0.225 28.3 13.5 18.2 A 0.108 9,4 4,3 A LOS ANGELES • 15250 VENTURA 

253 2 15,4 A 0.263 31.6 18.3 23.1 A 0.101 9,6 3.8 A LOS ANGELES • 14724 VENTURA 

122 2 16.5 A 0.273 30,8 lle1 10.2 A 0.142 15.6 5.6 A GLENDALE • 633 E. BROADWAY 

264 2 21.0 A 0,206 16.4 6.9 10.8 A 0.108 9,0 2.4 A PASADENA • CIT MILLIKAN LIBRARY 

475 1 22.0 A 0,114 14,3 7.4 8.1 A 0.106 6,6 2.7 A PASADENA • CIT ATHENAEUM 

482 2 22.6 A 0.121 11.3 8.7 9.1 A 0,084 8,1 3.4 A ALHAMBRA • 900 SOUTH FREEMONT 

133 2 23.0 A 0.154 19.4 13e1 10.0 A o.o5a 6,0 3.8 A *HOLLYWOOD STORAGE • BASEMENT 

135 1 23.0 A 0.217 21.1 14.7 9.3 A 0.119 5.0 3.0 A *HOLLYWOOD STORAGE • P,E. LOT 

181 2 26.5 A 0.147 17.6 12.0 10.0 A 0,086 9,0 4.1 A LOS ANGELES • 1640 SOUTH MARENGO 

125 1 27.0 A 0.152 17.9 3.4 13.1 A 0,102 11.7 2.8 A LAKE HUGHES ARRAY 1 • FIRE STATION 
262 1 32.0 A 0.150 14.2 3.8 14.5 A 0.105 7.8 ?.4 A PALMOALE • FIRE STATION 

288 2 33.0 A o.111 17.5 14e8 9.1 A 0.047 6.7 4.0 A VERNON • CENTR~L MFG. TERMINAL 

244 2 36.0 A 0 .• 035 ll.B e.8 o.o A 0.047 ~.9 3.9 A LOS ANGELES • 8639 LINCOLN 

247 2 37.0 A 0.045 13.3 10.3 o.o A 0.025 5.7 3.5 A LOS ANGELES • 9841 AIRPORT BLVD 

229 2 37.0 A 0.069 13.8 9.4 4.6 A 0.028 5.4 3.6 A LOS 4NGELES • 5250 CENTURY BLVD 

269 1 41.0 A 0.148 5.4 2.5 10.2 A 0.056 2.3 h7 A PEARRLOSSOM • PUMPING PLANT 

1052 1 49.0 A 0.112 8.5 2.3 6.0 A o.041 3.8 1.2 A 050 PUMPING PLANT 

411 1 54.0 A 0.043 5.0 3.4 o.o A 0.020 2.2 1.3 A PALO~ VERDES • 2516 VIA TEJON 

131 2 58.o A 0.028 9.6 7.3 o.o A 0.015 6.1 3.6 A LONG BEACH • UTILITIES BLDG. 

132 2 58.o A 0.038 9.c; e.o o.o A 0.027 4.9 3.8 A LONG BEACH • STATE COLLEGE 

476 2 58.o A o.o4o 5.A 2.7 o.o A 0.017 2.3 1.9 A fULLERTON • 2600 NUTWOOO AVE. 

130 1 59.0 A 0.030 10.4 8.7 o.o A o.o16 4.2 2.8 A LONG BEACH • TERMINAL ISLAND 

272 1 62.0 A 0.027 7.3 4.9 o.o A o.o11 3.2 2.2 A PORT HUENEME • NAVY LABORATORY 

472 2 66.0 A 0.033 8.5 6.5 o.o A 0.020 3.9 2.5 A ORANGE • 400 We CHAPMAN 

281 2 70.0 A 0.029 a.o 5.7 o.o A 0.020 2.4 1.7 A SANTA ANA • ORANGE CO. ENG. BLnG 

114 2 78.0 A 0.036 7.0 6.9 o.o A 0.010 3.5 2.3 A COSTA MESA • 666 w. NINETEENTH 

1102 1 82.0 A 0.034 2.5 2.1 o.o A 0.015 2.4 3.3 A WHFFLER RIDGE • GROUND STATION 

112 1 8B.o A 0.030 A o.o13 A CEnAR SPRINGS • PUMP PLANT 

113 1 91.0 A 0.039 2.6 1.3 o.o A 0.026 1.5 1.3 A COLTON • s. CAL. ~DISON CO. 

274 2 93.0 A 0.047 3.5 1.3 o.o A o.o19 1.5 o.a A SAN BERNARDINO • HALL Of RECORDS 

465 1 104.0 A o.044 4.6 2.4 o.o A 0.022 3.4 1.6 A SAN JUAN CAPISTRANO • CITY HALL 

123 1 134.0 A 0.044 2.9 1.7 o.o A 0.027 2.3 1.3 A HEMET • FIRE STATION 

103 1 168.0 A 0.037 2., 1.2 o.o A 0.015 1.4 1. 1 A ANZA • ANZA POST OffiCE (.,.) 

-o 

490413 1955 PUGET SOUNDt WASHINGTON MAG = 7.1 

SOIL STATIONS: ******** HORIZONTAL ******** ****** VERTICAL ****** 

STA• ST~UC DIST AC ACCEL VEL DISP OUR SRC ACClL VF.:L DISP SRC STATION LOC~TION 

2101 1 48.0 c 0.306 21.4 }0.4 22.3 A 0 .ll1 7.0 4.0 A OLYMPIA • HIGHWAY TEST LAB 

2170 1 69.0 c 0.072 8.2 2.7 14.8 A 0.024 2.4 2.3 A SEATTLE ARMY BASE • 4735 E MARGINAL 

590818 637 HEBGEN LAKEt MONTANA MAG = 7.1 

ROCK STATIONS: ******** HORIZONTAL ******** ****** VERTICAL ****** 

STA• STRUC OIST AC ACCEL VEL OISP I')UR SRC ACCEL VEL DISP s~c STATION LOCA liON 

2201 1 175.0 c 0.043 R 0.021 B BUTTFt MONT. • SCHOOL Of MINES 

2202 2 208.0 c 0.013 R o.oo8 B HELENAt MONT. • CARROL COLLEGE 

2204 1 454.0 c o.oo1 R o.oo1 B HUNGRY HORSE • DOWNST~EAM STATION 

SOIL STATIONS: ******** HORIZONTAL ******** ****** VERTICAL ****** 

STA# STRUC OlST AC ACCEL VEL DISP OUR SRC ACCf.L VEL OISP SRC STATION LOCATION 

2205 2 95.0 c o.055 B o.026 B BOZEMANt MONT. • STATE COLLEGE 
~ 

0 

520721 1152 KERN COUNTYt CALIFORNIA MAG a 7.2 

ROCK STATIONSI ******** HORIZONTAL ******** ****** VERTICAL ****** 

STAN STRUC DIST AC ACCEL VEL DISP OUR SRC ACCt:.L VEL DISP SRC STATION LOCATION 

136 2 115.0 B 0.032 B o.oos B •LOS ANGELES • SUBWAY TERMINAL 

1083 1 148.0 B 0.014 ~ o.oo9 B SAN LUIS OBISPO • CITY REC. BLDG 

SOIL STATIONSI ******** HORIZONTAL ******** ****** VERTICAL ****** 

STAt STRUC DIST AC ACCEL VEL OISP OUR SRC ACCEL VEL DISP SRC STATION LOCATION 

1095 1 42.0 B 0.196 17.7 9.1 19.6 A 0.123 6.7 5.0 A TAFT • LINCOLN HS TUNNEL 

283 1 85.o B 0.135 19.3 5.8 13.8 A o.051 5.0 2.1 A SANTA BARBARA • COURTHOUSE 

133 2 107.0 B o.o58 9.4 5.9 0.1 A 0.024 4.2 2.2 A •HOLLYWOOD STORAGE • BASEMENT 

135 1 107.0 B 0.062 8.9 6.4 0.1 A 0.022 3.1 3.4 A *HOLLYWOOD STORAGE • P.E. LOT 

475 1 109.0 B 0.054 9.1 2.9 0.1 A 0.033 4.5 3.0 A PASADENA • CIT ATHENAEUM 

288 2 122.0 B 0.037 R 0.012 B VERNON • CENTRAL MFG. TERMINAL 

131 2 145.0 B 0.016 R o.oo6 8 LONG BEACH • UTILITIES BLDG. 

113 1 156.0 B 0.014 B 0.012 B COLTON • S. CAL. EDISON CO. 

1008 1 224.0 8 o.018 A 0.006 R BISHOP • LA WATER DEPT GARAGE 

277 2 282.0 B o.oos R 0.001 8 SAN DIEGO • LIGHT & POWER 

1028 1 293.0 8 Oe010 B o.005 B HOLLISTER • CITY HALL 

2001 1 359.0 B o.004 ~ HAWTHORNE • US NAVY AMMO. DEPOT 

1081 2 366.0 B o.oo4 A SAN JOSE • BANK OF AMERICA HLDG 

117 1 370.0 B o.oo4 R o.ooJ B EL CENTRO • IRRIGATION SUBSTA. 

1049 2 407.0 8 0.001 A OAKLAND • CITY HALL 

1078 2 425.0 B 0.004 A SAN FRANCISCO • SOUTHERN PACIFIC BG 

720730 2145 SITKAt ALASKA MAG • 7.6 

ROCK STATIONSI 

STAt STRUC 

2714 1 

2708 1 

SOIL STATIONSI 

STAI\I STRUC 

2715 1 

******** HORIZONTAL ******** ****** VERTICAL ****** 

DIST AC ACCEL VEL DISP OUR SRC ACCEL VEL OISP SRC 

45.0 B 0.110 A o.o5o 8 

145.0 B 0.010 A 

******** HORIZONTAL ******** ****** VERTICAL ****** 

DIST AC ACCEL VEL OISP OUR SRC ACCEL VFL OISP SRC 

Joo.o 8 0.010 B 

SOURCES OF STRONG MOTION DATA 

CODE REFERENCE 

A EARTHQUAKE ENGINEERING RESEARCH LABORATORY (1969•1975) 

8 u.s. DEPT. OF COMMERCE !SERIAL PUBLICATION) 

C CLOUD ANU KNUDSON !NO DATE) 

D U. s. GEOLOGICAL SURVEY 11974) 

STATION LOCATION 

SITKA, ALASKA • MAGNETIC OR~ 

JUNEAU, AUKF BAY • BUR OF CO~M FISH 

STATION LOCATION 

YAKUTAT, ALASKA - AIRPORT PU~P HOUSE 

E A· G. ARADY IU. S. GEOLOGICAL SURVEY, WRITTEN COMMUN., 1977) 

F u. s. COAST AND GEODETIC SURVEY A~O EARTHQUAKE ENGINEFRING RESEARCH 

LABORATORY 11968) 

G u. s. GEOLOGICAL SURVEY 11975) 

H MALEY AND OTHERS (1975) 

I U. S. GEOLOGICAL SURVEY 11976A) 
LISTING Of STATIONS 

STAt STRUC GEO LOCATION STRUCTURE REf GEOLOGY REf 

103 1 s ANZA • ANZA POST OffiCE 1 STORY BLDG 1 ALLUVIUM 2 

104 2 R ARCADIA • SANTA ANITA RESERVOIR ABUTMENT, C DAM 1 GRANITE/DIORITE 2 

110 1 R CASTAIC • OLD RIDGE ROUTE INST SHELTER 1 SANDSTONE 1 

111 1 R CEDAR SPRINGS • ALLEN RANCH 1 STORY BLDG 1 GRANITIC 2 

112 1 s CEDAR SPRINGS • PUMP PLANT 1 STORY BLDG 1 SHALLOW ALLUVIUM 2 

113 1 s COLTON • s. CAL. EDISON co. 1 STORY BLDG 1 DEEP ALLUVIUM 1 

114 2 s COSTA MESA • 666 We NINETEENTH 18 STORY BLDG 1 ALLUVIUM- 1 

116 1 R DEVILS CANYON • fiLTER PLANT 1 STORY BLDG 1 LS/GNEISS 2 

117 1 s EL CENTRO • IRRIGATION SUBSTAe 2 STORY BLDG 1 >Jon M ALLUVIUM 1 

118 2 s LOS ANGELES • 16661 VENTURA 8 STORY RC BLDG 1 8M ALLUV/SHALE 1 

121 2 R fAIRMONT STATION • RESERVOIR ABUTMENT, E DAM 1 GRANITE 1 

122 2 s GLENDALE • 633 E. BROADWAY 3 STORY BLDG 1 >8 M ALLUVIUM 1 

123 1 s HEMET • fiRE STATION 1 STORY BLDG 1 ALLUVIUM 1 

125 1 s LAKE HUGHES ARRAY 1 • fiRE STATION 1 STORY BLDG 1 300 M ALLUVIUM 1 

126 1 I( LAKE HUGHES ARRAY 4 • CWR SITE INST SHELTER 1 WEATHERED GRANIT 1 

127 1 H LAKE HUGHES ARRAY 9 • CWR SITE 1 STORY BLDG 1 GNEISS 1 

128 1 R LAKE HUGHES ARRAY 12 • CWR SITE 1 STORY BLDG 1 THIN ALLUVIUM 1 

129 2 s LOMA LINDA- UNIV. MED. CENTER 10 STORY 8LDG 3 APP 250 M ALLUV 3 

130 1 s LONG BEACH • TERMINAL ISLAND 1 STORY BLDG 1 DEEP ALLUVIUM 1 

131 2 s LONG ~EACH • UTILITIES BLDG. 4 STORY BLDG 1 DEEP ALLUVIUM 1 

132 2 s LONG BEACH • STATE COLLEGE 9 STORY BLDG 1 >15 M ALLUVIUM 1 

~ 133 2 S * HOLLYWOOD STORAGE • BASEMENT 14 STORY RC 1 130 M ALLUVIUM 1 

135 1 S * HOLLYWOOD STORAGE • PeE• LOT INST SHELTER 1 130 M ALLUVIUM 1 

136 2 R * LOS ANGELES • SUBWAY TERMINAL 12 STORY 8LDG 3 120 M SHALE 3 

137 2 ~ * LOS ANGELES • WATER ~ POWER 15 STORY STEEL 1 MIOCENF SILTSTNE 2 

141 1 I< LOS ANGELES • GRiffiTH ORSERVATORY INST SHELTER 1 GRANITE 1 

181 2 s LOS ANGELES • 1640 SOUTH·MARENGO 7 STORY RC 1 >16 M ALLUVIUM 1 

190 2 I< LOS ANGELES • 2011 ZONAL 9 STORY RC 1 ALLUVIUM 0•10 M 1 

220 2 R LOS ANGELES • 3838 LANKERSHIM 20 STORY RC l SH &. SS 1 

229 2 s LOS ANGELES • 5250 CENTURY BLVD 7 STORY'STEEL 1 >16 M ALLUVIUM 1 

241 2 s LOS ANGELES • 8244 ORION 7 STORY RC 1 >13 M ALLUVIUM 1 

244 2 s LOS ANGELES • 8639 LINCOLN 12 STORY RC 1 >18 M ALLUVIUM 1 

247 2 s LOS ANGELES • 9841 AIRPORT BLVD 14 STORY RC 1 >23 M ALLUVIUM 1 2~3 2 s LOS ANGELES • 14724 VENTURA 12 STORY RC 1 >24 M ALLUVIUM 1 

259 2 s LOS ANGELES • 16055 VENTURA 12 STORY BLDG 1 12M ALLUV/SHALE 1 

262 1 s PALMDALE • fiRE STATION 1 STORY BLDG 1 ALLUVIUM 2 

264 2 s PASADENA • CIT MILLIKAN LIBRARY 9 STORY RC 1 APP 300 M ALLUV 2 

266 1 I< PASADENA • CIT SEISMOLOGY LAB 2 STORY BLDG 1 GRANITE 1 

267 2 s PASADENA • CIT JPL LAB 9 STORY STEEL 1 SANOY GRAVEL 2 

269 1 s PEARBLOSSOM • PUMPING PLANT INST SHELTER 1 130 M ALLUVIUM 2 

270 1 R PERRIS • RESERVOIR INST SHELTER 1 ALLUV VEN/GRANIT 2 

272 1 s PORT HUENEME • NAVY LABORATORY 1 STORY WAREHSE 1 >300 M ALLUVIUM 1 

277 2 s SAN DIEGO • LIGHT &. POWER 4 STORY BLDG 1 DEEP ALLUVIUM 1 

274 2 s SAN BERNARDINO • HALL Of RECORDS 6 STORY BLDG 1 >35 M ALLUVIUM 1 

278 2 I< SAN DIMAS • PUDDINGSTONE RESERVOIR ABUTMENT•EARTH 1 VOL CLASTICS•SH 2 

279 2 R SAN fERNANDO • PACOIMA DA~ ABUTMENT•CONCRET 1 JOINTED GNEISS 2 

280 1 R SAN ONOfRE • SCE NUCLEAR PLANT 1 STORY WAREHSE 1 SOFT SANDSTONE 1 

281 2 s SANTA ANA • ORANGE CO. ENG. BLDG 3 STORY BLDG 1 ALLUVIUM 1 

282 1 R GOLETA • UC fLUID MECHANICS LAB 1 STORY BLDG 1 4 M ALLUV/StLTST 1 

283 1 s SANTA BARBARA • COURTHOUSE 2 STORY BLDG J >10 M ALLUVIUM 1 
288 2 s VERNON • CENTRAL MFG. TER~INAL 6 STORY ALDG 1 DEEP ALLUVIUM 1 

290 1 R WRIGHTWOOD • 6074 PARK DRIVE 2 STORY BLDG 1 ALLUV VEN/IGN 2 

319 2 S * LOS ANGELES • UCLA ENGINEERING BLDG 4 STORY fROG 3 21 M ALLUVIUM 3 

411 1 s PALOS VERDES • 2516 VIA TEJON 2 STORY BLDG 1 SHALLOW SANDS/SH 2 

458 2 s LOS ANGELES • 15107 VAN O~EN 1 STORY RC 1 >23 M ALLUVIUM 1 

461 2 s LOS ANGELES • 15910 VENTURA 18 STORY STEEL 1 >12 M ALLUVIUM 1 

465 1 s SAN JUAN CAPISTRANO • CITY HALL 1 STORY BLDG 1 ALLUVIUM 2 

466 2 s LOS ANGELES • 15250 VENTURA 12 STORY RC 1 >12 M ALLUVIU"-1 1 

472 2 s ORANGE • 400 W. CHAPMAN 19 STORY BLDG 1 >100 M ALL/SHALE 2 

475 1 s PASADENA • CIT ATHENAEUM 2 STORY RC 3 APPROX 200 M ALL 3 

476 2 s FULLERTON • 2600 NUTWOOD AVE. 10 STORY RC 1 >20 M ALLUVIUM 1 

482 2 s ALHAMBRA • 900 SOUTH FREE~ONT 12 STORY STEEL 1 APPROX 100 M ALL 2 

497 2 s LOS ANGELES • 16633 VENTURA 14 STORY BLDG 1 ALLUVIUM 1 

512 2 s LOS ANGELES • 16255 VENTURA 12 STORY BLDG 1 20M ALLUV/SHALE 1 

610 2 s LOS ANGELES • 18321 VENTURA 10 STORY BLDG 1 >5M ALLUVIUM 1 

655 1 R JENSEN FILTER PLT • 13100 BALBOAt LA 2 STORY BLDG 1 ROCK 1 

657 2 s SANTA MONICA • 201 OCEAN 18 STORY BLDG 1 SOIL 1 

1001 1 s APEEL ARRAY • STATION 1 INST SHELTER 1 210M ALLUVIUM 1 

1002 1 s APEEL ARRAY • STATION 2 INST SHELTER 1 8M MU0/85M ALLUV 1 

1004 1 s BAKERSFIELD • HARVEY AUDITORIUM AUDITORIUM 1 >250 M ALLUVIUM 1 

1008 1 s BISHOP • LA WATER DEPT GARAGE 1 STORY BLDG 3 200 M ALLUVIUM 3 

lOll 1 s BUENA VISTA • GROUND STATION INST SHELTER 1 ALLUVIUM 2 

1013 1 s CHOLAME•SHANOON ARRAY NO. 2 INST SHt:LTER 1 45 M ALLUV/SS 1 

1014 1 s CHOLAME•SHANOON ARRAY NO. 5 INST SHELTER 1 ALLUVIUM 1 

1015 1 s CHOLAME•SHANOON ARRAY NO. A 1 STORY BLDG 1 THIN ALLUVIUM/55 1 

1016 1 s CHOLAME•SHANDON ARRAY NO. 12 INST SHELTER 1 30 M TERRACE/55 1 

1023 1 s FERNDALE • OLD CITY HALLt BROWN ST 2 STORY RLDG 1 ALLUVIUM 1 

.l::o. 

1\) 1027 1 R EDMONSTON • GROUND STATION INST SHELTER 1 5 M ALLUV/GNEISS 2 

1028 1 s HOLLISTER • CITY HALL 1 STORY BLDG 3 13 M ALLUVIUM 3 

1032 1 R SAGO CENTRAL • HARRIS RANCH INST SHELTER 1 ROCK 6 

1049 2 s OAKLAND • CITY HALL 15 STORY BLDG 3 76 M MUO•ALLUVIU 3 

1051 1 R OROVILLE SEISMOGRAPH STATION 1 STORY BLDG 1 META VOLCANICS 1 

1052 1 s 050 PUMPING PLANT INST SHELTER 1 ALLUVIUM 2 

1057 1 w PLEASANT HILL • DIABLO VALLEY COL• 2 STORY BLDG 3 2 M ALUV/SS 3 

1065 2 s SAN FRANCISCO 

- ALEXANDER BLDG 15 STORY ALDG 3 46 M ALLUVIUM 3 

1071 2 s SAN FRANCISCO • BETHLEHEM PAC BLDG 14 STORY BLDG 1 70M ALLUVIUM 1 

1074 2 H SAN FRANCISCO • 390 MAIN 1 STORY ALDG 1 SHALE/55 1 

1078 2 s SAN FRANCISCO • SOUTHERN PACIFIC BG 12 STORY RLDG 3 90 M FILL•ALLUV 3 

1080 2 s SAN FRANCISCO • STATE BLOG 1 STORY BLDG 3 61 M ALLUVIUM 3 

1081 2 s SAN JOSE • RANK OF AMERICA BLDG 13 STORY BLDG 3 APPROX 750 M ALL 3 

1083 1 R SAN LUIS OBISPO • CITY REC. BLDG 2 STORY BLDG 1 2 M LOAM/FRAN SH 2 

1093 1 s SAN PABLO • CONTRA COSTA COLLEGE 2 STORY BLDG 3 6 M FILL•ALLUV 3 

1095 1 s TAFT • LINCOLN HS TUNNEL 1 STORY SCH BLDG 1 ALLUVIUM 1 

1096 1 R FORT TEJON 

- CWR SITE 1 STORY BLDG 1 GRANITE 1 

1102 1 s WHEELER RIDGE • GROUND STATION INST SHELTER 1 APPROX 1no M ALL 2 

1117 1 R SAN FRANCISCO • GOLDEN GATE PARK INST SHELTER 3 FRAN CHERT-SHALE 3 

1202 1 s STONE CANYON EASTt CALIF. 1 STORY BLDG 1 SOIL 8 

1249 1 R CAPE MENDOCINO CC5) • PETROLIA INST SHELTER 1 CRETACEOUS ROCK 1 

1250 1 s GILROY (C6) • GEOL BLDGt GAL COL 1 STORY BLDG 1 TERRACE DEPOSITS 1 

1278 1 R SHELTER COVEt STA 2 CC41) • PWR PLT INST SHE.LTER 1 FRANCISCAN ROCK 1 

1291 1 s MARYSVILLE CCS6) • COOT MAINT BLDG 1 STORY BLDG 1 lOOM ALLIJVIU"4 1 

1292 1 s CHICO CC57) • 2334 FAIR STREET !STORY BLDG 1 90~ ALLUVIUM 1 

}.293 1 R PARADISE CC58) • KE~G TRNSMTR BLDG 1 STORY BLDG 1 VOLCANIC ROCK 1 

1377 1 s SAN JUAN BAUTISTA CC126) • 24 POLK 1 STORY 8LDG 1 SOIL 6 

1398 1 s PETROLIA CC156) • GENERAL STORE INST SHELTER 1 ALLUVIUM 1 
1438 1 R 

2001 1 s 

2005 2 s 

2101 1 s 

2170 1 s 

2201 1 ~ 

2202 2 R 

2204 1 R 

2205 2 s 

2707 1 H 

270A 1 R 

2714 1 R 

2715 1 s 

1501 1 s 

.llo. 

w 

CHOLAME•SHANOONI TEMBLOR INST SHELTER 

HAWTHORNE • US NAVY AMMO, DEPOT 1 STORY BLDG 

MOJAVE GENERATING PLANT LRG POWER PLANT 

OLYMPIA • HIGHWAY TEST LAB INST SHELTER 

SEATTLE ARMY BASE • 4735 E MARGINAL 1 STORY BLDG 

BUTTE• MONT, • SCHOOL OF ~INES 2 STORY BLDG 

HELENA, MONT, • CARROL COLLEGE 5 STORY BLDG 

HUNGRY HORSE • DOWNSTREAM STATION INST SHELTER 

BOZEMAN• MONT, • STATE COLLEGE 3 STORY BLDG 

FAIRBANKS, ALASKA • UNIV OF ALASKA INST SHELTER 

JUNEAUt AUKE BAY • BUR OF COMM FISH 1 STORY BLDG 

SITKA• ALASKA • MAGNETIC CBS, INST SHELTER 

YAKUTAT, ALASKA - AIRPORT PUMP HOUSE 1 STORY RLDG 

MANAGUAt NIC, • ESSO REFINERY 1 STORY BLDG 

REFERENCE LISTING 

CODE REFERENCE 

1 

2 

U. S. GEOLOGICAL SURVEY (19768) 

MALEY AND CLOUD (19731 

1 ROcK 

1 ALLUVIUM 

3 APPROX 70 M ALLU 

1 ALLUVIUM 

1 ALLUVIUM 

3 GRANITIC INTRUS 

3 GRANITICS 

3 LIMESTONE 

3 APPROX 170 M ALL 

3 SCHIST 

1 SLATE 

1 GRAYWACKE 

1 GLACIAL OUTWASH 

4 ALLUVIUM 

3 

4 

R, P, MALEY (U, s. GEOLOGICAL SURVEYt WRITTEN COMMUN,, 19751 

VALERA (1973) 

5 

6 

7 

8 

9 

TRIFUNAC AND BRADY !19751 

JENNINGS AND ST~AND <1959) 

JENNINGS AND STRAND (19691 

R, P. MALEY <U, s, GEOLOGICAL SURVEY, ORAL COMMUN,t 19771 

CLOUD AND PEREZ (19671 

9 

1 

3 

5 

5 

3 

3 

3 

3 

3 

1 

1 

1 

4 

* U.S. GOVERNMENT PRINTING OFFICE : 1978 689-035/41 




BOORE AND OTHERS--ESTIMATION OF GROUND MOTION PARAMETERS--GEOLOGICAL SURVEY C