Geophys. J . Int. (1990) 100, 285-301
Coda-Q distribution in the Iberian Peninsula
L. G. Pujades,' J. A. Canas,' J. J. Egozcue,'M. A. Puigvi,' J. Gallart:
X. Lana,2 J. Pous2 and A. Casas3
'Escuela Tecnica Superior de Ingenieros de Caminos, Canales y Puertos, Universidad Politkcnica de Catalunya, Jordi Girona Salgado 31, 08034
Barcelona, Spain
2Departamento de Fiiica de la Tierra, Facultat de Fiiica, Universidad de Barcelona, 08028 Barcelona, Spain
'Facultat de Geologia, Universidad de Barcelona, 08028 Barcelona, Spain
Accepted 1989 August 13. Received 1989 July 25; in original form 1989 April 13
SUMMARY
Several attenuation studies have established a frequency dependence law of the
anelastic attenuation factor Q in the form Q = Qo(f/fo)v for the approximate
1-10 Hz frequency range. We propose a method that leads to the determination of
Q,, which is a function of the reference frequency fo, and the real exponent v with a
single station. To carry out the problem we determine a set of master curves as a
function of Y. We discuss the method, and the different features of the master
curves, when it is applied to the complicated regions of the Iberian Peninsula and to
several instruments with different responses. Using this new method and the
seismographic stations available in the Iberian Peninsula we have mapped iso-Qo
lines, at a reference frequency of 1Hz,applying inversion methods. The Q, values
determined for Iberia vary between about 100 and about 600. Values close to 100
correspond to the southern part of Iberia. In general, Q, values increase from south
to north with values about 600 near the NW part of Iberia. The Pyrenees Mountains
and adjacent areas present Q, values between about 200 and about 350. These
results suggest a strong Qo lateral variation in Iberia. A considerable frequency
dependence of coda-Q has also been determined. The v values vary between 0.3 and
0.8. The Q, values obtained in the Iberian Peninsula show very good agreement
with several Q, values obtained in other regions of the world. Comparison between
the iso-Q, lines and other geophysical parameters, like regional variations of P,,
velocities, heat flow, isoseismal intensity distribution and crustal thickness, indicates
that lower Q , values are associated with higher isoseismal intensity attenuation,
higher heat flow, lower P,, velocities and thinner crust.
Key words: attenuation coda waves, Iberian Peninsula, iso-Q distribution.
INTRODUCTION
During the last two decades a number of geological and
geophysical investigations have increased our knowledge of
different properties of the crust and upper mantle in the
Iberian Peninsula (e.g. Payo 1972; Mueller et al. 1973;
Banda & Ansorge 1980; Vegas & Banda 1982; Mezcua &
Mdrtinez Solares 1983; Udias & Buforn 1985; Arenillas &
Bisbal 1986). These studies have shown that important
lateral heterogeneities exist in the crust and upper mantle of
this region. Coda-Q studies in the Iberian Peninsula also
indicate that there are important variations of the anelastic
attenuation, which is higher in the southeast, the Betic
realm, and in the northeast, in the F'yrenees Mountains,
than in the northwest, in the Hercynian basement (e.g.
Canas et al. 1987; Canas et al. 1988; Herraiz & Mezcua
1984). However, some of these studies do not take into
account the frequency dependence of Q; it seems that Q
increases with increasing frequency, from body-wave data
(e.g. Aki 1982).
The increase in Q values with frequency, for short-period
data, may be due to the effect of elastic scattering by the
lateral heterogeneities concentrated in the shallow-pwt of
the Earth. Short-period waves are particularly sensitive to
the path details. Aki (1969) suggested that the later portion
of a local or regional seismogram, the coda waves, may be
considered to be a result of back-scattered waves from
numerous heterogeneities distributed in the Earth's crust
and upper mantle.
A great number of theoretical and observational studies
285
286
L. G . Pujades et al.
support the validity of the Aki & Chouet (1975)
single-scattering model for coda waves (Scheimer & Landers
1974; Herrmann 1980; Aki 1982; Singh & Herrmann 1983).
Although studies performed by Frankel & Clayton (1986)
and Frankel & Wennerberg (1987a) do not support the
validity of the Aki & Chouet (1975) single-scattering model
and although there is still controversy about the idea that Q
increases with frequency in the crust (e.g. Frankel &
Wennerberg 1987b), we use the single-scattering model
because this work is based on the one carried out by Singh
& Herrmann (1983) that supports the validity of the Aki &
Chouet (1975) model. Finally, it is interesting to note that
the special features of coda waves have been widely used by
seismologists to obtain magnitude-duration formulae for
regional earthquakes (Bisztricsany 1958; Soloviev 1965;
Tsumura 1967; Lee, Bennett & Meagher 1972), and to
estimate seismic moment (Herrmann 1980; Singh &
Herrmann 1983), spectral scaling laws of local earthquakes
and local Q (Aki & Chouet 1975; Rautian & Khalturin
1978; Herrmann 1980). An excellent review of theoretical
and observational results about coda waves can be found in
Herraiz & Espinosa (1986).
1 MASTER CURVES DETERMINATION
The extension of Aki's (1969) coda wave theory carried out
by Herrmann (1980) leads to an estimate of local and
regional coda-Q values from the observed coda predominant
frequency fp as a function of the time t. The main
assumption of Herrmann (1980) is to suppose that the fp-t
coda wave relation is due to three different effects; the
source spectrum, the instrument response and the Earth Q
filter. The effect due to the source may be avoided by using
earthquakes with corner frequencies greater than the peak
frequency of the instrument or using data below the comer
frequency of the source spectrum. Herrmann (1980) showed
that for the World Wide Standard Seismograph Network
(WWSSN) the condition is achieved by using earthquakes of
magnitude m blower than 5.0. Therefore, it can be supposed
that the fp-f relation in the coda, observed by Aki (1969),
was due to the combined effects of the instrument response
and the Earth Q filter. The main purposes of this part of the
paper are: (a) to review the determination of coda-Q master
curves following Herrmann (1980), and (b) to determine a
new set of master curves following the procedures described
in Section 1.2.
1.1 Short review of Herrmann's (1980) method
Theoretical coda dispersion curves can be obtained by
searching for the predominant frequencies fp which make
the following function a maximum:
@(f, t ) = I(f)e-"f("Q)
(1)
where Z(f) is the instrument response, Q the apparent
regional attenuation, and t the difference between the origin
time of the earthquake and the time at which the coda are
observed.
The coda wave predominant frequencies can be obtained
by maximizing expression (1) to obtain the following implicit
dispersive relation:
where t* = t / Q , Z(fp) is the instrument response and Z'(fp) is
its first derivative.
Expression (2) allows for the computation of a set of
master curves: fp - t*. Taking total derivatives on both sides
or expression (2), it follows that
(3)
We can use (3) to compute the Herrmann (1980)
theoretical 'coda shape' curves, C(fp, t*), used by Singh &
Herrmann (1983) to obtain the spatial anelastic attenuation
coefficient y.
1.2 The frequency dependence: a new interpretation
Aki & Chouet (1975) and Rautian & Khalturin (1978) noted
a frequency dependence of Q from their study of coda
waves. In the short-period range, coda-Q is permitted to be
frequency dependent according to the power law (Herrmann
1980)
where fa is a reference frequency, Q, is the quality factor
obtained for f =fa, f is the frequency in Hz and v is a real
exponent.
At this point it is important to note that we are dealing
with two different frequencies, and consequently with two
different meanings: one is the frequency f used in the coda
filter-expression (1)-and
the other is the predominant
frequency fp that we obtain by maximizing expression (1); in
addition, fp is the frequency we read on the seismograms.
We must be careful to distinguish between f and fp. We have
two possible interpretations for the frequency-dependent
case as follows.
(i) In terms off,
(ii) In terms of fp,
Q(fp, v ) = Qdfo)(F)v
where Q, is the quality factor obtained for fp =fa.
In the first case, the master curves, fp-t,*, where t,* = t/Q,,
are given by
(7)
This method was proposed by Herrmann (1980) and has
been used by several authors (e.g. Singh & Herrmann
1983).
From expression (7) it can easily be seen that for each fp-t
pair and for fp =fa, the Q, obtained depends on t and v. Q,
can change with the lapsed time t , but it must remain
constant with respect to Y . Using expression (7), Q,
Coda-Q in the Iberian Peninsula
287
Figure 1. Master curves fp-t* for the new frequency dependence model for TOL station.
depends on v ; therefore, Q, is not a constant, contrary to
the hypothesis expressed by (5) or by (6). It is clear that for
v = 1 and for any lapsed time, t, Q, = 0 (singular point).
Singh & Herrmann (1983) avoided this incongruence
(trade-off between Q, and v ) by using pairs of seismograph
stations with different response characteristics-WWSSN
and Long Range Seismic Measurements (LRSM)
networks-located near one another. They calculated Q,
values for v = 0 using WWSSN seismograph stations. The
Q, value obtained for each WWSSN station was then
assigned to the corresponding LRSM station to obtain the
different Y values.
One way to obtain master curves in which Q, values d o
not depend on v, in agreement with the hypothesis given by
expression (5) or expression (6) and avoiding the trade-off
problems mentioned before, is to consider that Q follows
expression (6). In this sense, as will be seen later, this is one
way-using only one seismograph station-to perform the
procedure of Singh & Herrmann (1983) to avoid the
trade-off problem between Q, and Y mentioned above.
Therefore, using the second hypothesis, the new master
curves become
In this case, for each fp-t pair and for f,=f,, the Q,
values obtained depend on the lapsed time t, as expected,
but do not depend on v, in agreement with expressions (5)
and (6). It is important to note that different Q, values
correspond to different reference frequencies. Note also
that expressions (7) and (8) are exactly the same for v = 0.
Fig. 1 presents the new set of master curves corresponding
to Toledo station (T0L)-WWSSN
instrument-btained
from expression (8), and using the fp frequency dependence
hypothesis given by (6). The numerical values used to
construct the curves are shown in Table 1. Figs 2(a) and
Table 1. Numerical values employed to construct &-ti and coda
shape master curves for Toledo (TOL).fp is the predominant
frequency, S, is the instrument response normalized at 1 Hz and yp
and ys are the first and second derivatives, respectively. fp-t* and
C(fp, t*)-t* are master curves.
fP
1.550
1.505
1.460
1.415
1.370
1.325
1.280
1.235
1.190
1.145
1.100
1.055
1.010
0.965
0.920
0.875
0.830
0.785
0.740
0.695
0.650
0.605
0.560
0.515
0.470
0.425
0.380
0.335
0.290
0.245
0.200
0.155
0.110
Sd
1.475
1.466
1.452
1.432
1.407
1.376
1.338
1.294
1.242
1.184
1.120
1.050
0.976
0.897
0.817
0.735
0.654
0.574
0.498
0.426
0.359
0.297
0.241
0.192
0.149
0.112
0.082
0.057
0.037
0.023
0.012
0.006
0.002
YP
0.161
0.262
0.373
0.494
0.625
0.765
0.912
1.063
1.213
1.358
1.492
1.610
1.705
1.773
1.810
1.815
1.789
1.734
1.653
1.551
1.433
1.303
1.166
1.026
0.886
0.748
0.616
0.492
0.378
0.275
0.186
0.112
0.056
YS
-2.125
-2.351
.-2.582
.-2.809
-3.019
-3.195
-3.316
-3.36G
-3.304
-3.128
-2.820
-2.382
-1.825
-1.177
-0.476
0.235
0.915
1.527
2.049
2.465
2.774
2.981
3.096
3.130
3.094
3.000
2.853
2.658
2.419
2.137
1.814
1.453
1.058
t*
0.035
0.057
0.082
0.110
0.141
0.177
0.217
0.261
0.311
0.365
0.424
0.488
0.556
0.629
0.706
0.786
0.871
0.961
1.057
1.160
1.272
1.397
1.537
1.700
1.890
2.119
2.401
2.758
3.227
3.872
4.817
6.347
9.258
fp is the predominant frequency
Sd is the instrument response normalized at 1 hz
yp is the first derivative of Sd
ys is the second derivative of Sd
t* is given by expression ( 2 ) in the text
C(fp,t*) is the theoretical 'coda shape' curve
0.81E+01
0.55E+01
0.40E+01
0.29E+01
0.22E+01
0.16E+01
O.lZE+Ol
0.91E+00
0.67E+00
0.50E+00
0.37E+OO
0.27E+00
0.20E+00
0.15E+00
0.11E+OO
0.82E-01
0.61E-01
0.46E-01
0.34E-01
0.25E-01
0.19E-01
0.14E-01
0.963-02
0.67E-02
0.45E-02
0.3OE-02
0.18E-02
O.llE-02
0.593-03
0.293-03
0.12E-03
0.39E-04
0.83E-05
''
288
L. G . Pujades et al.
a
N
-
n
L
;loo
i
10-I
1 o-2
v
lo-'
-0.6
1 oo
tm ( s )
b
I
I
1o-2
10-I
1 oo
tm ( s )
Figure 2. (a) Master curvesf,-t* for WWSSN stations from Fig. 1 of Singh & Herrmann (1983). (b) Master curvesf,-?* for the new frequency
dependence model for WWSSN stations.
3(a), based on expression (7), show that the deduced Q,
values for fp =f, = 1Hz are different for different v values.
Figs 2(b) and 3(b), based on expression (8), show that the
Q, values for fp =f, = 1Hz are the same for any real value
of v.
The above considerations can be briefly explained by
considering that the calculated coda-Q values depend only
on the set of frequencies read on the seismograms (f,), and
do not depend on the whole frequency range (f).Although
the coda-Q values in the Earth depend on f, the calculated
coda-Q values are always obtained for a certain domain of
frequencies read on the seismograms. Therefore, in this
sense, Q is just a function of fp and is not a function off.
In both cases, the master curves for the frequency7'
dependent case are constructed in a straightforward way
starting from the frequency-independent case.
On a log-log plot, the first interpretation reduces to
(9)
and the second to
It must be observed that both sets of master curves have
Coda-Q in the Iberian Peninsula
289
8
I
I
-
1 on
N
a
L
1 0-1
I
10-I
1oo
tr ( s )
b
I
1 o-2
1 0-1
1 oo
tr ( s )
Figure 3. (a) Master curves fp-t* for LRSM stations from fig. 1 of Singh & Herrmann (1983). (b) Master curves fp-t* for the new frequency
dependence model for LRMS stations.
exactly the same pattern. The only difference between them
is that the term log(1 - v), in expression (9), causes a
displacement on the t: axis.
In order to compare the theoretical curves found from the
two mentioned hypotheses we have plotted the two sets of
master curves, corresponding to several Y ' S , for the
WWSSN and the LRSM instruments (Figs 2 and 3).
1.3 Comparison between Qo values determhed using the
two different sets of master curves
We have applied our model to the data of Singh &
Herrmann (1983). To illustrate the procedure, we present
the cases corresponding to figs 9 and 11 of Singh &
Herrmann (1983). We have digitized the data corresponding
to the LSNH seismograph station (LRSM network) and the
data of WES(WWSSN network), both located in the
northeastern United States. We have applied the same
scheme to the stations F'TOR (LRSM network) and LON
(WWSSN network) located in the northwestern United
States. Using the master curves in Figs 2(b) and 3(b),
corresponding to the Y values reported by Singh &
Herrmann (1983), for the above-mentioned cases (0.3 for
PTOR and LON, and 0.35 for LSNH and WES), the f,-t
data are graphically matched with the master curves. Q, is
that value of t which maps into to* = 1 s (since t: = t/Q,)
290
L. G. Pujades et al.
b
-
0
N
-
I
lo
a
L
10-I
1 o1
1 o2
t.
10'
( s )
Figure 4. (a) Plot off, (Hz) versus t (s) for the WWSSN station, LON. Q, = 300-400, v = 0.3 (data from fig. 11 of Singh & Herrmann 1983
(b) Plot of fp (Hz) versus t (s) for the LRSM station, PTOR. Q, = 450-550, v = 0.3 (data from fig. 11 of Singh & Herrmann 1983).
(Herrmann 1980). The obtained fits between theoretical and
observed data are good. Determined values are; Q, = 300400 and v = 0.3 for LON, and Q, = 450-550 and v = 0.3 for
PTOR. For stations WES and LSNH the determined values
are; Q, = 800-1100 and Q, = 900-1700, respectively, for a
common v value of 0.35. Singh & Herrmann (1983)
determined Q, = 300 and v = 0.3 for LON and F'TOR, and
Q,, = 900 for v = 0.3-0.4 for WES and LSNH. As explained
in section 1.2, the Q, values determined by Singh &
Herrmann (1983) were obtained using only the WWSSN
stations and then these values were assigned to the
corresponding LRSM stations. Table 2 shows these values
and Figs 4 and 5 show the fits. No error bars are given for
data points in Fig. 4 because no errors on fp and t were
calculated (Singh, S., personal communication). Our results
Table 2. Comparison between several Q, values determined b
Singh & Herrmann (1983) and the corresponding ones using th
methodology proposed in this work.
After Singh anc
Herrmann (19831
This work
Station
Po
PO
Northwestern United States
LON (WWSSN)
PTOR (LRSN )
0.3
0.3
300-400
450-550
0.0
0.3
300
300(*
Northeastern united States
(WWSSN)
LSNH (LRSfl )
WES
(*)
0.35
0.35
800-1100
900-1700
0.0
0.3-0.4
These values were assumed to be the same
as those obtained for the WWSSN stations
900
900(*
Coda-Q in the Iberian Peninsula
291
b
Figure 5. (a) Plot of fp (Hz) versuks I (s) for the WWSSN station, WES. Q, = 800-1100, v = 0.35 (data from fig. 9 of Singh & Herrmann,
1983). (b) Plot of fp (Hz) versus t (s) for the LRSM station, LSNH. Q, = 900-1700, v = 0.35 (data from fig. 9 of Singh & Herrmann 1983).
do not differ much from the results of Singh & Herrmann
(1983). As stated previously, expressions (7) and (8) are
exactly the same for v = 0. Therefore, Q, values obtained
by Singh & Herrmann (1983) for Y = O must be close to
those determined using expression (8), which is independent
of v. Some of the observed differences can be attributed to
the fact that we are using the data points obtained from figs
9 and 11 of Singh & Herrmann (1983). Another reason that
may explain why the results are reasonably comparable is
that the v values are small (about 0.3); therefore, obtained
Q, values, using both sets of master curves, must not differ
so much. Higher differences would be expected for values of
v close to 1 because the lower the value of the term (1 - v)
in expression (7), the greater the difference between the to
values in expressions (7) and (8) becomes.
1.4 Principal features of the new master curves
There are some interesting features which we would like to
discuss about the new master curves in order to clarify the
advantages and limitations of the method.
(i) All of them pass through fp = 1Hz (supposedly the
reference frequency-see Fig. 1).
(ii) They have horizontally asymptotic behaviour at the
292
L. G. Pujades et al.
1oo
R
(L
10-1
1 o-l
10''
1oo
tm
Figure 6. TOL theoretical master curves for a reference frequency of 10 Hz.
peak frequency of the magnification curve (Figs 1 and 6),
which acts as a filter cut-off.
It seems clear that if the frequencies are near l H z , it
will not be easy to evaluate the frequency dependence
because of the insensitivity of expression (8) to the real
exponent when fp =fo = 1Hz and therefore (fP/fn)" = 1 for
every v value. We can also expect that scatter in the data
generates instability problems in the estimates of v values.
Finally, we would like to make some comments about the
reference frequency. It is not possible to change the
reference frequency fo in order to increase the resolution of
the method. Fig. 6 presents the theoretical curves for fo
equal to 10 Hz. We only obtain a displacement of the curves
on the log-t axis, but their shape remains unchanged; this is
because the real exponent v is not dependent on the
reference frequency. In fact, linearizing (8) we have
Expression (11) is an operative expression and permits the
estimation of Q, and v parameters using just a single
station. The success of this method depends on both the
resolution of master curves and the scatter in the data.
Expression (12) shows how the resolution of this method
does not depend on the reference frequency fo.
2 APPLICATION TO T H E I B E R I A N
PENINSULA
2.1
Data analysis
We have used 427 vertical-component short-period seismograms corresponding to earthquakes located in or near the
Iberian Peninsula, and recorded in 13 stations distributed
over continental Iberia. All the earthquake locations are
obtained from the earthquake catalogue Boletin de Sismos
Pr6ximos edited by the Instituto GeogrAfico Nacionalroutine agency measurements. For all the studied
earthquakes, errors in origin time are always less than about
1s, and errors in the source-station distances are no more
than 10 km. A detailed list of stations, earthquakes and their
characteristics is given in table A1 of the Appendix. Fig. 7
presents two examples of the vertical-component shortperiod seismograms used in this study. Fig. 8 presents the
epicentre-station paths used in this work. We have
employed full size copies ftom the records and have used
optical magnification instruments to read in the fp-t pairs.
To avoid errors in the seismogram readings, we have read
those parts of the seismograms where the individual
frequencies appear clearly; therefore, peaks, troughs or
zero-crossings inside an assumed time interval can be read
without doubt. The time interval-always in the range of
5-10s-i~ chosen in such a way that an exact number of
cycles can be counted. In this way we avoid taking into
account fractions of a cycle.
The maximum measurement e r r o r d u e to the time
readings on the seismograms-using the optical magnification instruments is about fO.10 s. The induced error for the
average frequency corresponding to the particular time
interval is very small. For example, for the time interval
shown in Fig. 7(a) the associated error is about f0.02 s-'.
The standard deviation associated with the average fp
obtained for each time interval can be evaluated using the
individual frequencies contained in the different time
intervals. Therefore, all the average frequencies have their
associated corresponding standard deviations. For the time
interval shown in Fig. 7(a), the average frequency is about
1.16 s-l and its associated standard deviation is f0.03s-'.
The source-station distance errors do not affect the
determination of local Q values using fp-t data. These errors
Coda-Q in the Iberian Peninsula
293
b
Figure 7. Examples of vertical component short-period seismograms used in this study. (a) Recorded at the EBR (Ebro) Seismographic
Station. Earthquake; 1980 June 22 (see Table A l ) . The time length between the arrows indicates one example of the time interval to
determine the predominant frequency. (b) Recorded at the ALM (Almeria) Seismographic Station. Earthquake; 1980 September 27 (see Table
Al).
(less than about 10 km) may affect the determination of the
Qo distribution for Iberia (see next section). In any case, as
pointed out at the end of section 2.2, the highest standard
deviation associated with the mislocation error is 15 units of
Qo.
It must be said that, in all the calculations that follow, fp
and t are considered together with the errors mentioned
above.
The following algorithmic process was systematically
applied to data from each station.
(i) Analytical fit of the experimental instrument response
curve, using a non-linear inversion method to match the
experimental curve (Pujades 1987).
(ii) Construction of master curves fp-t* and C(f,, t*).
From step (i), a mathematical formula has been determined
for the instrument response curves. Therefore, expressions
(2) and (3) are solved analytically for the different
seismographs in the Iberian Peninsula. Fig. 9 shows the
magnification curve of Toledo Observatory (TOL) and its
analytical fit, normalized at a reference frequency of 1Hz.
The numerical values used for the construction of the coda
shape curve and the fp-t* master curves, for Toledo station
(TOL), are shown in Table 1. S, is the instrument response,
normalized at 1Hz, and y, and y , are the first and second
derivatives, respectively. From this table, and in order to
analyse the frequency dependence, we can easily construct
both master curves; those suggested by Herrmann (1980)
and those introduced here, using expressions (7) and 8)
respectively. Fig. 10 shows ' the seismograph st; ion
distribution and the principal tectonic provinces in the
9
1 O0
$ 1
E
0-'
L
0
C
- 0 10-2
Ln
I
10 - 3 t
- 91
-
0
-' 5,
171
1o-2
- 3*
-
l*
*1*
t
3'
I
I ~ I I WI ~IIIMI II!M I dtj
I Ill
1 I I
I Ill
1 I Ill
I
1 0-1
1oo
Preq.
(HZ 1
1 o1
h
Figure 8. Station-epicentre paths distribution
Figure 9. Analytical fit (solid line) to the instrument response curve
for ToledeTOL- (dots).
L. G . Pujades et al.
294
total errors in time and frequency-as mentioned before,
errors due to the origin time of the earthquake are very
small-are
lower than 1 s and lower than 0.03 s-l,
respectively; therefore, error bars appear only for a reduced
set of frequencies. The s u e of the points without error
barehorizontal and vertical-is larger than their associated
errors. fp and t, in Fig. 11, enter into the calculations
together with their estimated standard deviations discussed
before. Fig. 12 shows preliminary coda-Q, attenuation
values at 1Hz; they have been obtained for each station
using data from sources at different azimuths and distances.
LI
I ,
,
e.0
,
,
,
,
4-
.
.
,
,
0'
,
.
.
,'
.4
Figure 10. Seismograph stations used in the study and principal
tectonic units in the Iberian Peninsula. (1) Pyrenees Mountains, (2)
Mesozoic Basins, (3) Hercynian Massif, (4) Iberian Chain, (5) Betic
Alpine Ranges, ( 6 ) Tertiary Basins.
Iberian Peninsula. The stations SFS, MAL, ALM, CRT and
ALI are located in the high seismic region of the Betic
mountains system (Mezcua & Martinez Solares 1983).
Stations EPF and MLS, and LIS and PTO are located in the
Pyrenees Mountains and in the Portuguese Coastal region,
respectively; both regions present moderate seismic activity
(Mezcua & Martinez Solares 1983). The stations EBR, and
GUD and TOL are located inside the Catalonian coastal
mountains system with poor seismic activity and in the
aseismic Hercynian Massif (Mezcua & Martinez Solares
1983), respectively.
(iii) Determination of fp-f data from seismograms. The
predominant frequencies can be easily estimated by
counting the number of zero-crossings of the seismic trace
within a given time interval (as mentioned before, between
5 and lOs), and dividing the number of zero-crossings by
twice the window length in seconds.
(iv) Graphic estimation of regional Q. It is interesting to
note that we have been able to observe the presence of
important lateral heterogeneities and also the existence of
considerable frequency dependence. Herrmann (1980) and
Singh & Herrmann (1983) also noticed this fact. This
estimation procedure is independent of the one described
next. Generally, the graphic procedure is used to obtain a
first approximation to the Q, and Y values.
(v) The last step is to estimate simultaneously coda-Q,
and v values from a least-squares fit applied to expression
(11). The determination of Y values, in some cases, has been
difficult because sometimes it is impossible to discriminate
between the theoretical fp-f curves for frequencies near or
greater than fp = 1Hz (see Fig. 2b). Therefore, to avoid
problems in obtaining the Y values in these cases, we have
ignored the experimental fp-t data near or greater than
these frequencies. Afterwards, using the determined v
values, we have used all the data to obtain a better
estimation of the coda-Q, values. We have written v
without using confidence intervals when coda-Q, and Y
estimates were made in this way. Fig. 11 presents two
examples of the procedure to obtain Q, and Y values for the
southeastern part of the Iberian Peninsula. The data points
are presented together with their standard deviations. The
A strong frequency dependence in the Iberian Peninsula
has been inferred. Y values between 0.6 and 0.8 have been
determined in the southern part of the Iberian Peninsula,
and 0.3-0.6 in the middle and northern parts. Values of 0.7
or higher have been obtained in the Pyrenees Mountains.
The highest attenuation is found in the southeast, in the
triangle formed by the seismographic stations CRT, MAL
and ALM (Fig. 10). In general, coda-Q, values tend to
increase towards the northwest.
Although the 1-Hz Q, values obtained for the different
regions of the Iberian Peninsula (Fig. 12) seem to indicate
the existence of anelastic lateral variation, we have
performed tests of hypotheses applied to the obtained Q,
values. A Kolmogorov test indicates that the error
distribution between theoretical and observed fp values (e.g.
Fig. l l ) , determined for the different areas of Iberia, follows
a normal distribution. Under this condition, the established
hypotheses tests are as follows.
The null hypothesis, or no lateral variation on Q, values
(H,), can be written as E(Q6) = E(Q&), where E stands for
expectation and i and j denote any two values of Q, in Fig.
12.
The alternative hypothesis, or the existence of Q, lateral
variation ( H I ) , can be written as: E(Qb) # E(Q6).
If the null hypothesis H, is.rejected in most of the cases
with low significances, it can be stated that lateral variation
on Q, in fact does exist.
The hypotheses tests have been applied to all possible Q,
pairs in Fig. 12. The results can be summarized as follows.
(i) When comparing Q, values from different regions of
Iberia (e.g. in Fig. 12 central and southern part, eastern and
western part, etc.) we can be confident at more than 95 per
cent that the H, hypothesis does not hold.
(ii) When comparing values obtained for the same
regions of Iberia and differing by more than about 10 units
of Q,, the H, hypothesis is rejected at a confidence between
85 and 95 per cent.
(iii) It can be stated that for values differing by less than
about 10 units (in Fig. 12 it can be seen that these values
correspond to almost the same geographical location), the
H, hypothesis may be accepted.
From the above, there is statistical evidence for Q, lateral
variation in Iberia; therefore, a Q, distribution will be
calculated in the next section.
2.2
Inversion for regional Q,
There are a number of ways to regionalize the Q, values
(Singh & Herrmann 1983). We can estimate Q, averages for
)Coda-Q in the Iberian Peninsula
295
aLm 10
93099
57056
,J
5 AZ
5 209.60
5 D L S t 5 127.38
\
103
1o'
t
(sec)
crt 6
Om32
68043
t
-<
AZ
5 356.90
Dist 5 199.11
(sec)
Figure 11. (a) Plots of fp (Hz) versus t (s) for ALM. Q,= 131 f 20; v = 0.62. (b) Plots of fp (Hz) versus t (s) for CRT. Q , = 101f 5 ;
v = 0.58 f 0.07. Vertical bars indicate standard deviations. Data points without vertical or horizontal bars indicate that the associated standard
deviations in time or frequency are lower than the size of the data points.
Figure 12. Average Q, distribution of coda waves obtained from
the different stations of the Iberian Peninsula. No standard
deviations are shown in this figure for clarity. In most of the cases
the standard deviations are less or equal to 20 units of Q,.
each station and set of events considering different distances
and azimuths. If there is a good epicentral distribution, this
method leads to a reliable estimate of attenuation for the
considered station. Usually the station-epicentre distribution is controlled by the seismogenic regions and by the
location of the seismographic stations. Therefore, we have
regions with a good epicentral distribution and others
without earthquakes. This fact, together with the existence
of overlapping areas, complicates the interpretation of the
obtained results. To model lunar coda waves, Malin (1978)
used the coda scattering models (Aki 1969; Aki & Chouet
1975) and supposed that the first-order scatterers affecting
the coda wave amplitudes, at a given traveltime, would form
an ellipse having earthquake and seismograph location as
foci; at later times the resulting ellipse would be large and
the coda waves would sample a large region. This fact would
permit the coverage of large areas and the study of areas
that are far from seismogenic regions. Knowing the
dimensions of ellipses, as a function of time, it is possible to
find the Q, value for each region by applying a least-squares
inversion. Each fp-t pair permits an estimate of the Q,
value, averaged for the entire elliptically sampled region. If
we divide the ellipse into small regions we can make up the
296
1
L. G. Pujades et al.
equation
z;=,
I
t
where ti is the time spent by coda waves in the region with a
quality factor Qi.
Equation (13) can be written as
Expression (14) corresponds to only one fp-t pair;
therefore, for n pairs it becomes a system of the form
where i = 1, . . . , rn, k = 1, . . . , n, rn is the number of
sub-regions, and n is the number of pairs or data points.
xi = l/Qi, and yk = (l/Qo)k is easily determined from t:/tk.
aki = t k i / tk is the fraction of the total travel path that
scattered waves spend in the ith sub-region of the elliptical
kth zone.
In fact aki are averaged values from all azimuths leaving
the epicentre. In compact form, equation (15) is of the form
Y=AX.
(16)
A least-squares estimate of x, in (16), is given by the
well-known inversion problem
(ATA)x = ATY
(17)
and hence
x =(A~A)-'A~Y.
(18)
To guarantee a non-singular inverse for matrix ATA, we
use a damped least-squares technique (Crosson 1976; Singh
& Herrmann 1983). We have been able to apply the
Figure 14. Iso-Q, lines map, from coda waves, for the entire
Iberian Peninsula.
inversion method directly to the entire Iberian Peninsula,
but we have also used sub-regions to reduce the variance of
the solution. In order to incorporate the results in the same
framework and, later, to connect them, we have constructed
a grid which will be the basis of the regionalization into
sub-regions (Fig. 13). We have chosen regions in such a way
that we are able to obtain average Q, values at each point of
the grid. In the inversion procedure a coda-Q, value is
calculated for every fp-t pair, taking into account that the v
values determined at the end of section 2.1 remain constant
for each seismograph station used. Therefore, the inversion
procedure accounts for the dependence of Q with distance
between the station and theiscatterers generating the coda
waves. Afterwards, a linear interpolation method is applied
to determine iso-Q, lines. Fig. 14 presents the results. The
iso-Q, lines are drawn at intervals of 50 units of Qo. This
interval is wide enough to avoid intersection between
adjacent iso-Q, lines plus or minus their associated standard
deviations. The standard deviation associated with the poor
determination of the source-station distances (less than 10
km) lies, in all cases, between 8 and 15 units of Q,. The
total standard deviations are always less than 25 units of Q,.
2.3
-9'
L
O
!I*
'
-5*
-3'
-1*
*1*
375 kn
Figure 13. Reference grid for coda-& regionalization.
+3*
Discussion
An interesting feature is observed when comparing Figs 12
and 14. The determined regional values, using the inversion
method in the Pyrenees Mountains, are lower than the
average regional values obtained directly from the stations.
Correig, A. M., (personal communication), using coda-Q
determination methods, found Q, values of about 100 and
lower in a small region located in the eastern part of the
Pyrenees Mountains (Fig. 10)-the
neogene basin of
Cerdanya. Gagnepain-Beyneix (1987), also using coda-Q
determination methods, estimated low Q, values in the
Pyrenees (Fig. 10). The range of distances in these studies
expands from a few km to about 70 km. In this work, we
Coda-Q in the Iberian Peninsula
have covered a wide range of distances (Fig. 8), but we have
restricted the inversion procedure to the region just covered
by the grid of Fig. 13. Averaged Q, values directly
estimated from stations sample larger areas than the
regionalized ones. Gagnepain-Beyneix (1987) also noted the
distance dependence of Q,. This may be explained by the
fact that local studies tend to sample shallow parts of the
crust where Q, values are lower. Since we are covering a
wide range of lapsed times from the origin time of the
earthquakes (from about 20 to 300s), the obtained Q,
values may be considered as representative for most of the
crust of the Iberian Peninsula.
The fact that Q, values are different for different regions
of the Iberian Peninsula shows an important correlation with
the degree of current tectonic activity reported by Udias
and Buforn (1985); nevertheless, Q, variations are within
the same order of magnitude. The lowest values (Q, = 100)
are in the southeast of the Iberian Peninsula, and in the
northeast, in the Pyrenean domain (Q, = 200); both regions
have alpine characteristics but with some different tectonic
evolution. The highest values are in the northwest, on the
Hercynian Massif. In spite of the size of the region of this
study, our results show that low Q, values are associated
with low P, velocities and low crustal-velocity values. Banda
(1988) obtained high P, velocities of about 8.3 km sC1 in the
northwest, and the lowest value of average crustal velocity,
6.0 km s-', in the southeast of the Iberian Peninsula. From
the above, it seems that there may be a correlation between
Q, values and the lateral variation of several geophysical
parameters. This fact can be observed in the Pyrenees area,
where we have the greatest crustal thickness, with a strong
lateral discontinuity between sites. We conclude that high
Q, values are related to high and maintained crustal
thickness and to high and maintained seismic wave
velocities.
One interesting feature that can be observed by
comparing Fig. 10 with Fig. 14 is the following. Generally,
the iso-Q, lines tend to be parallel to the structural outlines,
the Q gradients being higher in the direction perpendicular
to the structural trend.
Our results agree with isoseismal intensity patterns and
with seismic hazard studies in the Iberian Peninsula (e.g.
Mezcua 1982; Martin 1983). In general, relatively low Q,
values are found in areas with relatively high seismic hazard.
Other attenuation results, in and near the Iberian
Peninsula, agree with the 1-Hz Q, distribution determined
for Iberia (Fig. 14). Mezcua, Herraiz & Buforn (1984)
estimated a coda-Q value of 617, at S H z , from the
aftershock sequence of the 1977 June 6 Lorca earthquake
(SE Spain). The Q , value of 198 at 1Hz, determined from
coda waves, for the southern part of the Iberian Peninsula
(Canas et al. 1987) is consistent with the coda-Q attenuation
value and the frequency dependence found in this study for
the region under consideration. Canas et al. (1988), using
surface-wave data, show that Q, structure in tectonic areas
of the Iberian Peninsula are lower in the active regions than
in stable ones. They found Q, = 300 for the region located
between TOL and PTO and Q, = l o 0 for the region
TOL-MAL. Romacho, M. D., (personal communication),
studying Lg-Q for the Algerie-Malaga (MAL), the
Algerie-Porto (PTO) and the Algerie-Toledo (TOL) paths,
obtained values of 181, 244 and 208, respectively.
297
CONCLUSIONS
By using a new method that permits the estimation of
regional attenuation values of Q, and its frequency
dependence with a single station, we have obtained a
detailed crustal coda-Q, map for the entire Iberian
Peninsula. The most important results and conclusions of
this study are as follows.
(i) The iso-Q, lines map of the Iberian Peninsula shows
important lateral variations of Q,. The lowest Q, values are
found in the southeast, in the triangle MAL-CRT-ALM
located inside the internal Betics with values near 100. The
highest values are found in the northwest, in the Hesperic
Massif, with values of about 600. In the Pyrenees area, we
have found a local minimum of about 200 (Fig. 14).
(ii) The attenuation map reflects the tectonic framework
of the Iberian Peninsula, and separates the Hercynian
nucleus from the Alpine formations. Nevertheless, Q,
values remain within the same order of magnitude.
(iii) The iso-Q, lines, generally, tend to be parallel to the
structural outlines, so the Q gradient is stronger in the
direction perpendicular to the structural trend than in the
parallel direction.
(iv) From the assumption of the simple power law given
in (6), a frequency dependence is found in the range
0.3-3 Hz.As a result of this study we have found Y values of
0.6-0.8 for the southern part of the Peninsula, 0.3-0.6 in
the central and northern parts, and 0.7 or higher in the
Pyrenees. These values compare well with the 0.3-0.6 range
obtained in the tectonically active western part of the
United States (Singh & Herrmann 1983).
(v) By comparing our regional attenuation map with
several other crustal parameters, we conclude that the
correlation between large crustal thickness and low
attenuation, noted by others, is true when the large
thickness is maintained. Strong variations in the crustal
thickness are associated with low Q , values. High and
maintained values of crustal ayerage velocities, including the
P, velocity, correlate well with low attenuation.
(vi) There is a good correlation between our attenuation
map and studies of seismic hazard in different regions of the
Iberian Peninsula. This fact may permit use of the detailed
Q, map obtained in this study as an important input for
seismic risk analysis and engineering seismology (Singh &
Herrmann 1983).
Finally, it should be noted that in this study, no real
distinction has been made between intrinsic Q and scattering
Q. This is beyond the scope of this paper. The relationship
of coda-Q and intrinsic Q is certainly an area of growing
interest and discussion.
ACKNOWLEDGMENTS
We thank Robert Herrmann for giving us some of his
computer programs and for helpful comments, and Enric
Banda for valuable comments and critical review of the
manuscript. We also thank the Directors and personnel of
the different Seismological Observatories for their facilities
and help in obtaining seismograms and instrument response
curves used in this work. We also thank the anonymous
referees who helped to improve the final version of this
298
L. G . Pujades et al.
paper. The research reported in this paper was supported by
CAICYT, contract number 1151/84.
REFERENCES
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scattered waves, J. geophys. Res., 74, 615-631.
Aki, K., 1982. Scattering and attenuation, Bull. seism. SOC. A m . ,
72, S319-5330.
Aki, K. & Chouet, B., 1975. Origin of coda waves: source,
attenuation and scattering effects, J. geophys. Res., 80,
3322- 3342.
Arenillas, M. & Bisbal, L., 1986. Sismicidad y Riesgo Sismico en
Castellbn, Valencia y Alicante, pp. 51-76, Citedra Geologia
Aplicada a las Obras Pdblicas, ETSICCP de la UPV, Valencia.
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Earth. planet. Inter., 51, 222-225.
Banda, E. & Ansorge, J., 1980. Crustal structure under the central
and eastern part of the Betic Cordillera, Geophys. J . R . astr.
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Bisztricsany, E. A,, 1958. A new method for the determination of
the magnitude of earthquakes, Geofiz. Kozlem., 7, 2.
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657-662.
Canas, J. A., De Miguel, F., Vidal, F. & Alguacil, G., 1988.
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Frankel, A. & Clayton, R. W., 1986. Finite difference simulations
of seismic scattering: Implications for the propagation of
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1. geophys. Res., 91, 6465-6485.
Frankel, A. & Wennerberg, L., 1987a. Energy-flux model of
seismic coda: separation of scattering and intrinsic attenuation,
Bull. sekm. SOCA m . , 77,1223-1251.
Frankel, A. & Wennerberg, L. 1987b. On the frequency
dependence of shear-wave Q in the crust from 1 to 15 Hz,
EOS, Trans. A m . geophys. Un., 68, 1362.
Gagnepain-Beyneix, J., 1987. Evidence of spatial variations of
attenuation in the western Pyrenean range, Geophys. J. R. astr.
SOC.,89, 681-704.
Herraiz, M. & Mezcua, J., 1984. Application of coda wave analysis
to microearthquake analog data, Ann. Geophys., 2, 545-552.
Herraiz, M. & Espinosa, A. F., 1986. Scattering and Attenuation of
High-Frequency Seismic Waves: Development of the Theory of
Coda Waves, Open File Report 86-455, p. 92, US Geological
Survey, Denver, CO.
Herrmann, R. B., 1980. Q estimates using the coda of local
earthquakes, Bull. seism. SOC.A m . , 70, 447-468.
Lee, W. H. K.,Bennett, R. E. & Meagher, K. L., 1972. A method
of estimating magnitude of local earthquakes from signal
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Res., US Geological Survey, Menlo Park, CA.
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University.
Martin, A,, 1983. Riesgo sismico en la Peninsula Ibkrica, PhD
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320-344.
APPENDIX
Table A l . Sets of station-epicentres used in the study.
ALI
Date
20/ 3/79
11/ 5/79
14/ 5/79
30/ 6/79
36/ 6/79
30/ 7/79
27/ 8/79
29/ 9/79
2 5/10/7 9
23/ 4/80
16/ 5/80
20/ 5/80
ALM
Date
20/ 1/79
27/ 2/79
5/ 3/79
20/ 3/79
20/ 3/79
20/ 4/79
1/ 5/79
14/ 5/79
27/ 5/79
3/ 7/79
31/ 7/79
25/10/79
29/ 2/80
18/ 4/80
30/ 5/80
22/ 6/80
22/ 9/80
27/ 9/80
8/12/80
22/ 1/81
13/ 4/81
12/10/81
15/11/8 1
18/ 1/82
l a t = 38.3553 l o n
O r . Time
Lat.
21:53:59.3
22: 5:12.9
1:47:48.0
1:44:38.3
2: 7:27.5
0:55:24.7
4: 9:54.6
15:41:20.8
15:29:48.0
15:45:59.2
2:13: 3.8
0:38:41.1
lat
=
36.8525
37.19
37.58
37.60
40.40
40.57
37.10
38.06
38.22
38.01
38.17
38.55
38.47
lon
-
-0.4872
Lon.
-
-3.60
-1.23
-2.46
-2.57
-2.57
-3.60
-0.09
-0.49
-0.82
-0.87
-0.30
-0.69
h(km) mb
10 4.8
10 3.1
10 4.2
10 4.1
10 3.8
10 3.7
5 3.0
5 3.1
10 4.2
-- --5
4
2.8
3.2
-2.4597
Or. Time
Lat.
Lon.
5:53: 5.0
12:57:10.0
17:33:10.0
21:53:56.4
21:57: 3.4
15:28:24.5
13:49:53.6
1 :47: 46.1
19:41:16.7
7: 34 :39.5
21:43:20.3
15:29:48.5
20:40:50.6
11: 6: 6.2
16:32:58.8
23:18:33.9
13:35:12.0
19:39:15.3
6:51:23.2
21:29:41.4
10:58:28.3
2:13: 58.4
13:13:52.1
18:42:38.0
37.16
36.29
36.83
37.16
37.22
36.75
36.95
37.61
36.89
37.10
37.12
38.01
43.19
37.41
36.82
35.99
36.85
36.78
35.98
36.99
38.35
36.94
36.85
36.62
-3.38
-3.70
-2.50
-3.80
-3.79
-2.50
-5.42
-2.46
-3.82
-2.60
-3.60
-0.77
-0.36
-2.50
-3.12
-5.32
-2.45
-3.10
-2.12
-2.60
-0.82
-5.47
-2.46
-2.49
h(km) mb
5
8
-5
5
_&
24
5
5
5
5
20
5
20
5
--
-5
16
1
1
9
10
5
3.3
3.2
2.9
4.1
4.4
--4.0
4.2
3.5
2.3
3.9
4.2
4.9
3.8
4.0
4.7
2.6
4.3
4.3
4.0
3.4
5.0
2.9
3.2
Coda-Q in the Iberian Peninsula
22/ 6/82
25/ 6/82
6/11/82
31/12/82
CRT
Date
27/ 2/79
4/ 3/79
12/ 3/79
15,’ 4/19
1/ 5/79
1/ 5/79
1/ 5/19
1/ 5/79
1/ 5/79
11/ 5/79
12/ 5/79
14/ 5/79
14/ 5/79
14/ 5/79
14/ 5/79
22/ 5/79
4/ 6/79
16/ 6/79
16,’ 6/79
30,’ 6/79
30/ 6/79
1/ 7/79
7/ 7/79
13/ 7/79
1/ 8/79
2/ 8/79
9/ 8/79
9/ 8/79
9/ 8/79
12/ 8/79
27/ 8/79
19/ 9/19
19/ 9/79
28/ 9/79
28/ 9/19
25/10/79
26/11/7 9
27/11/79
13/ 3/80
10/10/80
22/10/80
11/11/8 0
6/ 1/81
lo/ 4/81
1/10/81
3/10/82
6/11/82
6/11/8 2
3/12/82
EBR
Date
1/ 3/16
3/ 6/76
10/ 6/76
iii 6/76
11/ 6/76
11/ 6/76
12/ 6/76
5/ 1/79
5/ 2/79
28/ 2/79
1/ 4/79
a/ 4/79
1/ 5/19
14/ 5/79
25/ 5/79
25/ 5/79
25,’ 5/19
20/ 6/19
1/ 7/19
6/ 7/19
30/ 1/79
l8/ 8/79
28/ 9/19
10/10/79
25/10/79
19:50:23.7
42.88
12: 0:40.9
36.80
16:32:24.1
37.20
5 ~ 2 3 ~ 5 2 . 0 36.53
lat
37.1900 l o n
-
-
-1.87
-3.13
-1.35
-2.23
-3.5979
Or. T i m e
Lat.
Lon.
12:57:10.0
13:39:51.5
3:18:49.7
21:44:12.6
12:16:53.8
12:56:41.8
13:17:32.1
13:49:53.6
20: 9:43.7
22: 5:12.9
22: 2:30.7
1 :45: 59.6
1 :47 :46.1
3:35: 4.9
21:35:42.0
13:52:42.5
22:29:28.8
16:10:51.3
16:21:20.8
1: 44 :28.3
2: 7:25.2
12:43:31.4
21:29:20.5
1:27: 0.0
7: 4:28.4
14: 5:54.0
11:46:42.1
12:47:59.5
12:51:50.0
9:16:23.9
4: 59:52.9
19:33:30.7
22:43: 4.3
9 :13: 16.7
10:25: 43.1
15:29:48.0
2: 49: 20.8
19:42:36.8
3: 7:22.5
23:37:26.1
12:29: 4.8
10:59:46.6
12:20:14.6
19:23: 6.0
17:17: 0.0
8: 34: 58.3
12:22:58.4
16:32:24.1
0:20: 2.5
36.29
36.95
35.56
37.19
36.95
36.37
36.48
36.96
37.06
37.59
37.63
37.11
37.60
37.16
36.39
36.51
36.44
37.26
37.19
40.40
40.42
36.55
36.95
37.18
31.15
37.19
37.26
37.28
37.18
37.13
38.00
37.10
36.85
37.26
37.96
38.01
38.28
38.31
36.37
37.94
36.33
37.82
31.78
37.65
37.65
37.35
38.45
31.20
39.42
-3.70
-3.60
-3.55
-4.62
-5.23
-5.09
-5.08
-5.42
-5.34
-1.23
-2.58
-2.82
-2.46
-2.83
-4.10
-2.98
-4.15
-3.71
-3.60
-2.57
-2.57
-3.10
-4.75
-3.60
-3.63
-3.63
-3.77
-3.74
-3.60
-3.53
-0.02
-4.00
-2.46
-3.19
-4.07
-0.82
-0.49
-0.50
-7.38
-0.92
1.40
-5.27
-1.73
-4.62
-7.33
-5.28
-1.75
-1.35
-0.55
lat
-
40.8206
lon
=
7
5
12
15
4.9
3.9
3.8
4.2
h(km) mb
8
5
9
5
10
5
10
24
5
10
5
20
5
26
--
5
9
5
5
10
10
10
10
--
--5
5
-5
5
5
22
5
5
20
20
2
20
10
5
5
1
1
5
10
10
12
24
3.2
2.2
3.1
3.2
3.1
3.2
3.1
4.0
3.1
3.1
2.8
2.4
4.2
2.8
2.8
3.3
3.0
2.6
2.6
4.1
3.8
2.5
2.6
2.3
2.0
1.8
3.2
3.3
2.0
2.5
3.0
3.8
3.6
2.4
2.8
4.2
3.1
4.0
3.3
2.8
Date
1/ 4/79
30/ 6/79
6/ 7/79
28/ 9/19
17/12/19
28/ 1/80
2/ 2/80
29/ 3/80
17/ 5/80
19/ 7/80
20/10/80
i4/12/ao
19/ 3/81
19/ 7/81
6/ 1/82
6/ 1/82
11,’ 4/82
12/ 4/82
7/ 5/82
22/ 5/82
22,’ 5/82
221 5/82
11/ 6/82
12/ 6/82
12/ 6/82
22/ 6/82
22/ 6/82
24/12/82
--3.9
3.1
3.8
5.1
Lat.
Lon.
h(km) mb
2:26: 1.8
15:25:14.0
3:24 :11.3
11:12: 913
21:53: 5.9
21:56:45.4
4:18: 3.5
17:20:12.8
22:52:26.6
11:50: 8.0
19: 4:29.1
4:22:38.5
13:49:53.6
1 :47: 46.1
1:43: 1.0
1:47:13.0
7:37: 6.0
0: 9: 6.4
10:47:12.8
11:59:51.8
0: 55: 25.8
0:36: 5.3
5:28:45.5
16:18:48.8
15:29:48.5
41.25
42.20
42.54
42.42
42.59
42.23
42.54
43.10
36.80
43.00
43.18
42.30
36.95
37.60
41.95
41.95
41.95
37.25
42.70
43.34
37.11
43.11
43.25
41.37
38.01
1.23
1.70
1.15
1.45
1.45
0.93
1.36
-0.50
-4.10
-0.20
-2.12
1.90
-5.42
-2.45
2.63
2.63
2.63
-3.49
2.00
-0.44
-3.67
-- 3.6
-- ---- 3.4
-- ---
0.80
0.45
-0.20
-0.17
-- ---- ---- --20 3.4
-- 3.6
-- 3.4
24
5
--
--
--
--
5
20
5
5
5
5
20
3.4
3.0
4.0
4.2
3.3
3.0
3.0
4.5
3.5
3.8
3.7
3.7
3.2
3.1
4.2
38.36
42.50
43.40
42.54
43.18
43.31
42.40
43.09
43.25
42.53
35.99
42.61
39.21
35.89
43.30
41.69
40.65
42.38
42.67
36.15
38.40
38.62
42.83
41.48
37.02
43.25
43.23
42.58
41.57
41.38
41.10
42.75
42.93
41.98
43.20
43.25
42.87
43.02
39.42
42.57
Or. T i m e
19: 4:29.1
2: 7:25.2
11:59:51.8
5: 28 :45.5
17:37:15.2
9:25:28.3
5:26:31.4
22:27:30.3
1:14:20.3
23:27:52.5
0: 30 :23.6
19: 5:59.6
15: 5:16.7
19:58:34.8
16:32:49.8
17:22:11.8
20:21:46.7
16:30:25.4
11:41:49.8
4: 3: 3.2
4: 37: 51.0
5: 59: 23.9
16:16:28.6
9 :59 :15.8
17:23:52.6
19:50:23.7
20:24:31.6
0: 6:16.8
l a t = 40.6430
GUD
Date
16,’
23/
25,’
20/
2:49:20.1
23: 2:30.0
17:37:15.2
9:25:38.3
20:40:50.6
22:58: 3.8
22:27:30.3
9:34:35.8
13:10:17.1
1: 14: 20.3
23:18:33.9
23:27:52.5
0:52: 1.4
13: 7:50.0
0: 30 :23.6
19: 5:59.6
18:15:45.8
3: 1:55.1
7: 55: 55.0
7:46:49.1
1 :21: 52.7
2: 37: 35.8
15:53: 5.9
11:52:37.4
8 :26:51.2
16:32:49.8
17:22:11.8
6: 52: 32.2
20:21:46.7
16:30:25.4
11:41:49.8
4: 3: 3.2
5:59:23.9
16:16:28.6
9: 59 :15.8
17:23:52.6
19:50:23.7
20:24: 5.5
0:20: 2.7
0: 6:16.8
l a t = 43.0308
4.1
4.1
4.1
OK. Time
--
EPF
---
0.4936
lo
26/11/79
5/12/79
17/12/79
28/ 1/00
29/ 2/80
29/ 2/80
29,’ 3/80
13/ 4/80
16/ 4/80
17/ 5/80
22/ 6/80
19/ 7/80
25/ 7/80
13/10/8 0
2 0/10/8 0
14/12/80
10/ 1/81
28/ 1/81
31/ 1/81
14/ 2/81
5/ 3/81
5/ 3/81
23/ 4/81
19/ 5/81
6/ 9/81
6 / 1/82
6/ 1/82
12/ 3/82
11,’ 4/82
12/ 4/82
7/ 5/82
22/ 5/81
22/ 5/82
11/ 6/82
12/ 6/82
12/ 6/82
22/ 6/82
22/ 6/82
3/12/8 2
2 4/12/8 2
2/84
2/84
2/84
3/84
lon =
-0.48
2.48
-0.50
2.42
-0.36
-0.38
2.40
2.40
-0.35
2.45
-5.32
0.13
0.59
1.62
-0.35
2.65
0.10
1.50
1.17
-9.07
0.07
0.08
1.82
2.57
0.68
-0.97
-0.98
0.12
3.18
3.33
1.70
-1.77
-2.05
0.63
-0.35
-0.40
-1.87
-1.92
-0.55
0.57
40
5
10
9
5
5
--
--
5
--5
5
5
5
5
5
1
1
5
18
5
--
5
10
5
10
18
16
7
14
5
10
15
5
14
5
7
5
24
5
299
3.1
3.5
3.5
3.6
4.9
3.1
3.3
3.3
4.3
3.8
4.7
3.5
3.0
--3.8
3.9
3.3
--3.6
4.5
4.9
3.7
4.1
--4.3
4.9
3.9
3.9
3.0
3.0
2.9
4.6
3.9
3.0
4.4
4.0
4.9
3.2
3.1
4.1
0.3400
Lat.
Lon.
43.15
40.54
43.36
43.25
43.40
42.54
41.24
42.40
42.53
42.55
43.29
41.70
42.60
43.13
43.25
43.23
41.57
41.38
41.10
42.75
42.84
42.93
41.98
43.20
43.25
42.87
43.02
42.57
-2.26
-2.53
-0.27
0.45
-0.50
2.42
-1.09
2.40
2.44
-0.10
-0.35
2.65
-1.40
-0.07
-0.97
-0.98
3.18
3.33
1.70
-1.77
-1.75
-2.05
0.64
-0.35
-0.40
-1.87
-1.92
-0.57
h(km) m b
10
5
20
5
10
9
5
--
5
5
5
5
--
lo
lo
18
7
14
5
10
5
15
5
14
5
7
5
5
3.4
3.8
3.8
3.2
3.5
3.6
2.9
3.3
3.8
3.5
3.8
3.9
2.8
--4.9
3.9
3.0
3.0
2.9
4.6
4.2
3.9
3.0
4.4
4.0
4.9
3.2
4.1
l o n = -4.1540
Or. T i m e
Lat.
Lon.
19: 1: 5.7
5:51:44.0
2: 3:18.4
23~32~42.7
37.50
43.18
43.22
38.10
-6.40
0.13
-1.13
-0.20
h(km) mb
-----
,
3.9
4.0
4.3
3.2
300
L. G . Pujades et al.
MAL
15/ 6/84
24/ 6/84
28,’ 6/84
13/ 7/84
2/ 8/84
10/ 8/84
29/ 8/84
29/ 8/84
12/ 9/84
13/ 9/84
13/ 9/84
13/ 9/84
13/ 9/84
13/ 9/84
13/ 9/84
26/ 9/84
28/ 9/84
29/ 9/84
8/10/84
17/10/84
LGR
Date
14/ 5/79
23/ 5/79
30/ 7/79
2 5/10/7 9
16/ 4/80
12/10/80
14/12/80
5/ 2/01
3/ 1/82
231 2/82
11/ 3/82
30/ 3/82
12/ 4/82
221 5/82
22/ 5/82
22/ 5/82
24/ 4/82
24/ 5/82
29/ 5/82
12,’ 6/82
12,’ 6/82
22/ 6/82
23,’ 6/82
5/ 7/82
21/ 8/82
25/ 8/82
24/12/82
31/12/82
LIS
12:24: 4.7
14:30:50.9
22:35:21.3
17: 7:18.9
13:40:23.0
4 :14:34.8
6:27: 30.7
23:30:12.4
13:53:43.0
4: 34 :lo. 0
9: ~ 8 -6.0
:
9: 56 :25.0
11:40: 4.0
12: 3:49.0
14:25:36.0
4: 54 :26.0
3: 2: 2.0
20:44:53.0
20: 4:56.0
17:38:33.0
lat
=
-2.00
-3.72
-0.57
-6.25
-0.23
2.73
-8.48
-0.98
-2.37
-2.30
-2 30
-2.22
-2.03
-2.28
-3.72
2.28
-5.25
-1.51
-1.38
-3.22
42.90
36.82
37.97
35.80
38.73
41.47
42.18
43.28
36.98
36.97
36.97
36.93
37.03
36.78
43.33
42.30
36.47
37.25
41.15
36.68
42.4578
lon
-
Lat.
Lon.
1: 7:4a.4
10:36:50.7
2: 7:27.5
15:29:48.0
13:10:27.8
11:13:14.3
19: 6: 1.4
21:57: 0.1
2:13:27.0
17:59:13.8
14:49:37.7
5: 1:47.9
10: 6: 5.6
4: 3: 3.2
4:37:51.0
5: 59:23.9
1:58: 0.2
21: 9:36.6
3:55: 8.2
9: 59 :15.8
17:23:52.6
19:50:23.7
22:14:40.5
1 :26:11.1
4: 7:45.5
20:59: 3.9
0: 6:16.8
20:42: 4.7
37.59
42.60
40.42
38.01
42.50
41.81
41.91
43.53
42.08
40.57
42.88
42.92
42.92
42.75
42.85
42.93
42.47
42.73
42.98
43.20
43.25
42.87
42.80
43.07
43.42
43.12
42.57
42.95
-2.46
-3.70
-2.57
-0.82
-
38.7164
Date
Or. Time
16/10/77
7/ 1/78
15/ 2/79
20/ 3/79
1/ 5/79
3/ 9/79
6/ 9/79
5/10/79
16/10/79
6/l lj79
22/12/79
29; 1/00
2/ 3/80
12/ 3/80
22/ 3/80
23/ 5/80
22/ 6/80
10/11/8 0
3/12/80
8/12/80
5/ 3/81
12/10/81
6/ 1/82
24/ 6/84
12/ 9/84
7:44:49.7
9:24:59.1
10:11:59.0
21:53:56.0
13:49:53.6
20:27:52.6
18:13:37.6
13:41:10.4
13: 1:56.4
~.....
17 :20 :45.0
23:45:12.2
3 :18:40.3
9: 13: 16.2
10:13: 5.7
18:47:59.0
6 :14: 30.5
23:18:33.9
2: 3:53.1
22:16:27.3
6: 51:23.0
1 :21: 52.7
2: 13: 58.4
16:32:49.8
14:30:50.9
4: 34 :lo. 0
lon
-0.88
-2.78
2.44
-0.72
-3.03
-2.68
-1.90
-1.95
-1.95
-1.77
-1.75
-2.05
-1.67
-1.92
-1.97
-0.35
-0.40
-1. a7
-1.77
-2.18
-1.85
-0.17
-0.57
-2.03
-
--------------------
3.2
5.0
3.5
3.3
3.8
3.5
3.3
3.8
4.1
5.0
4.1
3.7
4.4
4.1
3.5
4.5
3.9
3.1
3.3
3.5
-2.5033
OK. Time
lat
--
h(km) mb
10
--
10
10
5
5
5
5
10
5
7
10
5
10
5
15
5
10
15
14
5
7
5
10
10
10
5
15
4.2
3.0
3.8
4.2
3.3
2.5
3.4
4.2
3.1
4.1
3.8
3.3
3.2
4.6
4.2
3.9
3.9
3.7
3.4
4.4
4.0
4.9
3.8
3.4
3.4
4.1
4.1
3.5
Date
15/ 2/19
27/ 2/19
20/ 3/19
20/ 3/79
1/ 5/79
1/ 5/79
1/ 5/79
1/ 5/79
14/ 5/79
27/ 5/79
30/ 6/79
31/ 7/79
6/11/79
8/12/79
22/12/79
29/ 1/80
12/ 3/80
21/ 3/80
26/ 3/80
14/ 4/80
13/10/8 0
20/10/80
9/11/00
11/11/8 0
3/12/8 0
6/ 1/81
21/ 1/81
21/ 1/81
22/ 1/81
14/ 2/81
14/ 2/81
14/ 2/81
14/ 2/81
13/ 3/81
13/ 3/81
13/ 3/81
24/ 6/84
12/ 9/84
13/ 9/84
13/ 9/84
13/ 9/84
13/ 9/84
13/ 9/84
lat
-
36.7275
lon
-
-4.4111
OK. Time
Lat.
Lon.
10:12: 1.2
12:57:10.4
21:53:56.4
21:57: 3.4
12:16:53.8
12:56:46.9
13:17:32.1
13:49:54.0
1 :41:48.4
19:41:18.0
1:44:33.8
21:43:18.0
17:20:45.0
4: 51: 46.6
23:35:12.3
3:18:40.0
3: 7:22.5
22:16: 0.5
5:53:18.1
11: 6:ll.O
20:13:44.8
7:46: 4.8
22:40: 4.3
10:59:46.7
22:16:25.7
12:20:14.6
11: 4:22.4
11:15: 9.9
21:29:41.4
7: 46 :49.1
7: 55: 34.0
8: 32 :23.1
12:47:21.2
0:33: 0.3
5: 13:22.6
19:46:34.6
14:30:50.9
13:53:43.0
4: 34 :10 .O
9: 8: 6.0
9: 56 :25.0
11:40: 4.0
12: 3:49.0
42.89
36.30
37.16
37.22
36.95
36.40
36.48
36.93
37.60
36.89
40.40
37.08
39.06
36.73
35.06
36.29
36.31
36.89
36.84
37.00
35.85
37.20
17.16
37.87
31.04
37.78
36.87
36.75
37.00
36.15
36.13
36.13
36.42
36.22
35.50
36.13
36.82
36.98
36.97
36.97
36.88
37.03
36.78
-7.46
-3.63
-3.80
-3.19
-5.23
-5.24
-5.08
-5.42
-2.46
-3.81
-2.57
-3.72
-8.99
-4.86
-4.32
-8.04
-7.33
-3.77
-7.97
-2.89
-4.68
-7.70
-4.46
-5.27
-5.68
-1.73
-5.02
-4.82
-2.68
-9.07
-9. oa
-8.10
-5.85
-5.72
-3.92
-6.32
-3.72
-2.37
-2.30
-2.30
-2.22
-2.32
-2.28
h(km) mb
40
10
5
5
10
10
5
10
10
10
10
10
5
10
5
35
20
5
10
5
23
5
5
5
5
1
5
10
1
18
23
34
21
10
1
5
43
--
--
---
---
4.5
3.2
4.1
4.4
3.1
3.2
3.1
4.0
4.2
3.5
4.1
3.9
3.4
3.8
4.0
4.4
3.3
2.8
3.7
3.8
4.2
3.4
2.5
4.1
4.3
4.1
3.8
3.4
4.0
4.5
4.0
4.1
4.0
3.4
3.6
3.8
5.0
4.1
4.1
4.1
3.7
4.4
4.1
-9.1491
Lat.
Lon.
36.32
38.10
42.76
37.16
36.95
38.82
36.76
39.38
36.82
39.05
37.06
36.30
38.97
38.72
39.10
37.30
35.99
38.46
36.92
35.98
38.40
36.94
43.25
36.82
36.97
-10.82
-5.71
-7.31
-3.80
-5.42
-7.74
-9.35
-8.96
-7.97
-8.98
-4.34
-8.02
-8.16
-9.14
-8.00
-7.47
-5.30
-8.00
-5.67
-2.12
0.07
-5.47
-0.97
-3.72
-2.30
h(km) mb
20
5
10
5
24
5
14
10
10
5
40
35
10
18
4.7
3.9
4.6
4.1
4.0
4.2
3.3
3.6
3.6
3.4
4.0
4.4
3.3
2.4
-- --17 4.0
-- 4.1
20 --21
16
--
9
10
--
--
4.3
4.3
4.9
4.0
4.9
5.0
5.0
MLS
Date
1/ 4/79
30/ 6/79
18/ 8/79
10/10/79
17/12/7 9
20/ 1/80
2/ 2/80
29/ 3/80
17/ 5/80
19/ 7/80
20/10/80
14/12/80
19/ 3/81
19/ 7/81
6/ 1/82
6/ 1/82
11/ 4/82
7/ 5/82
22/ 5/82
22/ 5/82
22/ 5/82
22/ 6/82
lat
-
42.9558
lon =
1.0950
OK. Time
Lat.
Lon.
19: 4:29.1
2: 7:25.2
0:36: 5.3
16:18:48.8
17:37:15.2
9:25: 38.3
5:26:31.4
22:27:30.3
1: 14:20.3
23:27:52.5
0: 30: 23.6
19: 5:59.6
15: 5:16.7
19:58:34.8
16:32:49.8
17:22:11.8
20:21:46.7
11:41:49.8
94: 3: 3.2
4: 37: 51.0
5: 59:23.9
20:24: 5.5
43.18
40.54
43.17
41.37
43.40
42.54
41.20
42.40
42.53
42.60
43.30
41.69
42.60
43.13
43.26
43.24
41.57
41.10
42.74
42.84
42.93
43.02
-2.21
-2.58
0.81
-0.20
-0.50
2.42
-1.14
2.40
2.61
0.13
-0.35
2.65
-1.40
0.07
0.97
0.98
3.18
1.70
-1.77
-1.75
-2.05
-1.92
h(km) mb
10
5
5
5
10
9
5
-5
5
5
5
--
10
10
18
7
5
10
5
15
5
3.4
3.8
3.7
3.1
3.5
3.6
2.9
3.3
3.8
3.5
3.8
3.9
2.8
3.8
4.9
3.9
3.0
2.9
4.6
4.2
3.9
3.2
Coda-Q in the Iberian Peninsula
PTO
Date
18/12/66
18/12/66
26/11/67
20/ 4/73
7/ 6/73
8/10/73
11/ 3/74
28/ 3/74
10/ 1/75
6/ 8/75
15/ 4/76
16/10/77
7/ 1/78
12/10/78
12/10/78
15/ 2/79
16,’ 2/79
20/ 2/79
1/ 5/79
30/ 6/79
30/ 6/79
3/ 9/79
6/ 9/79
19/ 9/79
19/ 9/79
22/10/7 9
6/11/79
11/ 2/80
11/11/80
6/ 1/82
22/ 9/82
22/ 9/82
24/ 6/84
12/ 9/84
13/ 9/84
13/ 9/84
13/ 9/84
13/ 9/84
13/ 9/84
SFS
Date
5/ 2/79
1/ 5/79
1/ 5/79
23/ 5/80
21/ 1/81
14/ 2/81
14/ 2/81
14/ 2/81
14,’ 2/81
15/ 2/81
15/ 2/81
12/ 3/81
13/ 3/81
13/ 3/81
13/ 3/81
13/ 3/81
14/ 3/81
3/ 7/81
12/10/8 1
25/ 6/81
3/10/82
28/12/82
l a t = 41.1386
lon
=
-8.6022
Time
Lat.
Lon.
10:46:28.1
13:51:36.0
17:11:36.0
2:27: 3.8
20:55:28.0
21:28:20.6
5:25: 34.6
1: 38:36.7
2: 59:28.0
1: 32: 52.4
6: 1:40.6
7 :44: 49.7
9:24: 59.1
19:55:53.5
21: 1:55.1
10:12: 1.2
23:57:43.4
14:48:31.8
13:49:53.6
1:44: 38.3
2: 7:27.5
20:27:56.2
18:13:37.0
19:33:30.7
22:43: 4.3
10:21:52.0
17:20:47.6
17:16:48.8
10:59:46.6
16:32:49.8
20:36:55.7
21:52:11.8
14:30:50.9
13:53:43.0
4: 34 :10.0
9: 8: 6.0
9: 56: 25 .O
11:40: 4.0
12: 3:49.0
35.80
43.25
39.07
42.19
42.83
39.83
40.39
40.01
43.50
41.14
36.69
36.33
38.10
41.88
42.04
42.89
42.48
42.34
36.95
40.40
40.42
38.83
36.80
37.10
36.85
37.10
39.02
42.17
37.83
43.25
36.50
40.77
36.82
36.98
36.97
36.97
36.56
37.03
36.78
-7.60
-3.30
-3.47
-8.66
Or.
l a t = 36.4617
lon
-8.80
-7.34
-7.88
-8.57
-7.10
-8.20
-8.77
-10.82
-5.76
-7.73
-7.76
-7.46
-9.53
-7.93
-5.42
-2.57
-2.57
-7.96
-9.52
-3.97
-2.46
-4.41
-9.59
-8.19
-5.22
-0.97
-7.57
-8.42
-3.72
-2.37
-2.30
-2.30
-2.13
-2.32
-2.28
-
h(km) mb
40
49
4.0
--
3.8
---
5
3.6
3.3
2.5
4.1
3.1
3.3
3.6
4.1
4.7
3.9
4.3
3.6
4.5
4.0
3.4
4.0
4.1
--
5
5
14
--
5
5
20
5
5
5
40
10
10
24
10
10
5
10
5
22
10
5
5
5
10
30
10
--
-------
--4.2
3.3
3.8
3.6
3.8
3.4
3.4
4.1
4.9
3.3
2.8
5.0
4.1
5.0
4.1
3.1
4.4
4.1
-6.2054
Time
Lat.
Lon.
22:52:26.6
12:16:52.7
13:49:53.6
6:14 :30.5
20:38:39.3
7: 46:49.1
7: 55:34.0
8: 32:23.1
12:47:21.2
0:49: 3.1
4: 0:47.8
23:22:10.8
0: 30:24.7
0:33: 0.3
5: 13 :22.6
19:46:34.6
13:33:27.7
3: 31: 36.8
2 :13: 58.4
12: 0:40.9
8:14: 58.3
19:29:39.7
36.80
37.01
36.95
37.20
36.89
36.15
36.13
36.13
36.42
36.40
36.18
36.17
36.38
36.88
35.50
36.13
36.32
36.35
36.93
36.80
31.35
36.38
-4.10
-5.25
-5.42
-7.48
-4.72
-9.07
-9.08
-8.98
-5.85
-7.02
-5.65
-5.72
-5.97
-5.72
-3.92
-6.32
-5.75
-4 + 72
-5.47
-3.13
-5.30
-7.82
Or.
TOL
h(km) mb
-lo
24
17
1
18
23
34
21
20
20
g
25
10
1
5
5
34
9
5
10
40
3.6
3.1
4.0
4.0
4.0
4.5
4.0
4.1
4.0
3.0
3.0
_-3.4
3.4
3.6
3.8
3.7
3.9
4.0
3.9
3.9
4.1
Date
15/ 2/79
14/ 5/79
9/ 8/79
3/ 9/79
22/10/79
25>10;79
25jiij79
26/11/7 9
18/12/79
2/ 2/80
23/ 5/80
17/ 9/80
17/ 9/80
11/11/80
12/11/8 0
5/ 3/81
10/ 4/81
19/ 4/81
28/ 8/81
11/ 3/82
22/ 6/82
10/10/82
31/12/82
16/ 2/84
23/ 2/84
25/ 2/84
13/ 6/84
24/ 6/84
2/ 8/84
12/ 9/84
13/ 9/84
13/ 9/84
13/ 9/84
13/ 9/84
13/ 9/84
26/ 9/84
28/ 9/84
29/ 9/84
17/10/84
lat
=
39.8814
l o n = -4.0486
Time
Lat.
Lon.
10:12: 1.2
1:47:48.4
11:46:40.3
20:27:56.2
10:21:52.0
15:29:48.0
1: 56:27.8
2:49:20.8
5: 47: 36 .O
5: 26: 32.0
6:14 :30.5
4 :56: 30.0
5:26: 32.0
10:59:46.7
1: 2: 7.2
1 :21:52.7
19:22:24.7
12: 8:43.6
4: 4:43.4
14:49:37.7
19:50:23.7
3:19:59.5
20:42: 4.7
19: 1: 5.7
5: 51 :44 .O
2: 3:18.0
12:24: 4.7
14:30:50.9
13:40:23.2
13:53:43.0
4: 34 :lo. 0
9: 8: 6.0
9:56:25.0
11:40: 4.0
12: 3:49.0
4:54:26.0
3: 2: 2.0
20:44:53.0
17:38:33.0
42.89
37.60
37.47
38.83
37.10
38.01
36.84
38.28
42.84
41.24
37.19
40.00
41.24
37.83
40.78
38.40
37.65
38.27
37.67
42.88
42.87
38.87
42.95
37.50
43.18
43.22
42.90
36.82
38.73
36.98
36.97
36.97
36.93
37.03
36.78
42.30
36.47
37.25
36.68
-7.46
-2.46
-3.93
-7.96
Or.
-4.41
-0.82
-3.75
-0.49
-7.20
-1.09
-7.47
-0.98
-1.09
-5.27
-1.82
0.07
-4.62
-1.03
-3.63
-1.90
-1.87
-2.10
-2.03
-6.40
0.13
-1.13
-2.00
-3.72
-0.23
-2.37
-2.30
-2.30
-2.22
-2.32
-2.28
2.28
-5.25
-1.85
-3.17
h(km) mb
40
10
10
5
10
10
10
20
20
5
16
10
5
5
13
5
1
5
1
7
7
5
15
4.5
4.2
3.2
4.2
3.8
4.2
3.4
3.1
4.2
2.9
4.0
3.0
2.9
4.1
2.9
4.2
4.1
3.3
3.4
3.8
4.9
3.5
3.5
-- 3.9
4.0
-- 4.3
-- 3.2
-- 5.0
14 3.8
-- 4.1
-- 5.0
4.1
-- 3.7
-- 4.4
4.1
4.5
15 3.9
3.7
-- 3.5
--
--
----
301