-
Notifications
You must be signed in to change notification settings - Fork 0
/
Adib_14.m
374 lines (325 loc) · 15.3 KB
/
Adib_14.m
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
%% Purpose
% Search for precursors automatically for all detectable earthquakes with acceptable
% azimuthal angles accuracy by scanning 2 or 4 night time periods and all
% frequencies in ULF
%% Loading universal variables
load VARIABLES_WORLD
mag_min=5.0;
dis_max=180;
depth_max=200;
LT_start=[22,00,02,04];
LT_end=[00,02,04,06];
no_records=0;
%% Analysis starts
for stn_num=1:size(stn_vec,1)
for year=2005:2018
%% Checking files availability
stn=string(stn_vec(stn_num));
filepathname=strcat('E:\Study\MAGDAS DATA\',stn,'\',stn,string(year),'S.mat');
filecheck=exist(filepathname,'file');
if filecheck~=2 continue; end
disp(sprintf('Running on %s%d..',stn,year));
datenum_start=datenum([year,01,01,00,00,00]);
datenum_end=datenum([year,12,31,23,59,59]);
stn_latlon=[stn_MAGDAS(stn_num,2:3)];
region=string(station_vec(stn_num,2));
%% Building earthquakes table
EQ_table=NaN(1,11);
j=1;
for i=1:length(EQ_WORLD)
if datenum(EQ_WORLD(i,1:6))>=datenum_start && datenum(EQ_WORLD(i,1:6))<=datenum_end
EQ_table(j,:)=EQ_WORLD(i,:);
j=j+1;
end
if datenum(EQ_WORLD(i,1:6))>datenum_end
break;
end
end
i=1;
EQ_sel=NaN(1,8);
for j=1:size(EQ_table,1)
if EQ_table(j,10)>=mag_min
EQ_latlon=[EQ_table(j,7:8)];
EQ_dis=deg2km(distance('gc',stn_latlon,EQ_latlon));
EQ_time=datenum(EQ_table(j,1:6));
EQ_mag=EQ_table(j,10);
EQ_Ks=(10^(0.75*EQ_mag))/(EQ_dis+100);
EQ_depth=EQ_table(j,9);
EQ_angle=azimuth('gc',stn_latlon(1:2),EQ_latlon(1:2),'degree');
if EQ_dis<=dis_max && EQ_depth<=depth_max
EQ_sel(i,1)=EQ_time;
EQ_sel(i,2)=EQ_dis;
EQ_sel(i,3)=EQ_mag;
EQ_sel(i,4)=EQ_Ks;
EQ_sel(i,5)=EQ_depth;
EQ_sel(i,6:7)=EQ_latlon;
EQ_sel(i,8)=EQ_angle;
i=i+1;
end
end
end
EQ_selselidx=find( 0.025*EQ_sel(:,2)<EQ_sel(:,3)-4.5 | EQ_sel(:,3)>=6.5 | EQ_sel(:,2)<=30 );
EQ_selsel=EQ_sel(EQ_selselidx,:);
if isempty(EQ_selselidx)
disp('No detectable/significant earthquakes. Skipping..');
pause(0.5);
clc;
continue;
else
disp(sprintf('Found %d earthquake(s) to be analyzed',numel(EQ_selselidx)));
end
%% Loading geomagnetic data files
days_num=round(datenum_end-datenum_start);
if EQ_selsel(1,1)-datenum_start<60
disp('Previous year file need to be loaded..')
filepathname2=strcat('E:\Study\MAGDAS DATA\',stn,'\',stn,string(year-1),'S.mat');
if exist(filepathname2,'file')
matname(1)=strcat(stn,string(year-1),'S');
matname(2)=strcat(stn,string(year),'S');
A=load(matname(1));
B=load(matname(2));
H=vertcat(A.H,B.H);
D=vertcat(A.D,B.D);
Z=vertcat(A.Z,B.Z);
UT1m=horzcat(A.UT1m,B.UT1m);
H=H((end-(days_num+61)*86400)+1:end);
D=D((end-(days_num+61)*86400)+1:end);
Z=Z((end-(days_num+61)*86400)+1:end);
UT1m=UT1m((end-(days_num+61)*86400)+1:end);
disp('Previous year file has been loaded.');
prevyear=1;
else
matname=strcat(stn,string(year),'S');
load(matname);
H_nan=NaN(61*86400,1); D_nan=NaN(61*86400,1);
Z_nan=NaN(61*86400,1); UT1m_nan=UT1m(1)-61:1/86400:UT1m(1)-(1/86400);
H=vertcat(H_nan,H); D=vertcat(D_nan,D);
Z=vertcat(Z_nan,Z); UT1m=horzcat(UT1m_nan,UT1m);
disp('Previous year file is unavailable. Proceeding..');
prevyear=2;
end
else
matname=strcat(stn,string(year),'S');
load(matname);
prevyear=0;
end
datadatenum_start=min(UT1m); datadatenum_end=max(UT1m);
datenum_vec=datadatenum_start:floor(datadatenum_end);
days_vec=datetime(datenum_vec,'Format','dd/MM/yyyy','ConvertFrom','datenum');
days_num=length(days_vec);
date_vec=datevec(datenum_vec);
year_vec=unique(date_vec(:,1));
if prevyear==2 year_vec=year_vec(end); end
%% Removing noise/outlier
H_dn=H; D_dn=D; Z_dn=Z;
G_dn=sqrt(H_dn.^2+D_dn.^2);
for i=1:5
H_dn=medfilt1(H_dn,30,'omitnan','truncate');
D_dn=medfilt1(D_dn,30,'omitnan','truncate');
Z_dn=medfilt1(Z_dn,30,'omitnan','truncate');
G_dn=medfilt1(G_dn,30,'omitnan','truncate');
end
for i=1:5
H_sig=std(H_dn,'omitnan');
H_mu=mean(H_dn,'omitnan');
D_sig=std(D_dn,'omitnan');
D_mu=mean(D_dn,'omitnan');
Z_sig=std(Z_dn,'omitnan');
Z_mu=mean(Z_dn,'omitnan');
G_sig=std(G_dn,'omitnan');
G_mu=mean(G_dn,'omitnan');
for j=1:length(H_dn)
if H_dn(j)>H_mu+5*H_sig||H_dn(j)<H_mu-5*H_sig
H_dn(j)=NaN;
end
if D_dn(j)>D_mu+5*D_sig||D_dn(j)<D_mu-5*D_sig
D_dn(j)=NaN;
end
if Z_dn(j)>Z_mu+5*Z_sig||Z_dn(j)<Z_mu-5*Z_sig
Z_dn(j)=NaN;
end
if G_dn(j)>G_mu+5*G_sig||G_dn(j)<G_mu-5*G_sig
G_dn(j)=NaN;
end
end
end
%% Nighttime data in LT
for l=1:numel(LT_start)
LT_length(l)=LT_end(l)-LT_start(l);
if LT_length(l)<0 LT_length(l)=LT_length(l)+24; end
t_zone=timezone(stn_latlon(2),'degrees');
t_start(l)=LT_start(l)+t_zone;
if t_start(l)>24 t_start(l)=t_start(l)-24; end
if t_start(l)<0 t_start(l)=t_start(l)+24;end
t_starts(l)=t_start(l)*3600;
t_int(l)=LT_length(l)*3600;
for i=1:days_num
H_night(:,i,l)=H_dn(t_starts(l)+1:t_starts(l)+t_int(l));
D_night(:,i,l)=D_dn(t_starts(l)+1:t_starts(l)+t_int(l));
Z_night(:,i,l)=Z_dn(t_starts(l)+1:t_starts(l)+t_int(l));
G_night(:,i,l)=G_dn(t_starts(l)+1:t_starts(l)+t_int(l));
UT1m_night(:,i,l)=UT1m(t_starts(l)+1:t_starts(l)+t_int(l));
t_starts(l)=t_starts(l)+86400;
end
end
%% Spectrogram calculation
n_win=1800;
n_ovrlp=0.5*n_win;
n_fft=n_win;
fs=1;
for l=1:numel(LT_start)
for i=1:days_num
[H_spec,F_spec,T_spec]=spectrogram(H_night(:,i,l),'yaxis',hamming(n_win),n_ovrlp,n_fft,1);
[D_spec,F_spec,T_spec]=spectrogram(D_night(:,i,l),'yaxis',hamming(n_win),n_ovrlp,n_fft,1);
[Z_spec,F_spec,T_spec]=spectrogram(Z_night(:,i,l),'yaxis',hamming(n_win),n_ovrlp,n_fft,1);
[G_spec,F_spec,T_spec]=spectrogram(G_night(:,i,l),'yaxis',hamming(n_win),n_ovrlp,n_fft,1);
bin001=find(round(F_spec,4)==0.0100); bin01=find(round(F_spec,4)==0.1000);
H_spec1=H_spec(bin001:bin01,:);
D_spec1=D_spec(bin001:bin01,:);
Z_spec1=Z_spec(bin001:bin01,:);
G_spec1=G_spec(bin001:bin01,:);
F_spec1=F_spec(bin001:bin01);
Z_spec_mu(:,i,l)=mean(abs(Z_spec1),2);
G_spec_mu(:,i,l)=mean(abs(G_spec1),2);
ZG(:,i,l)=Z_spec_mu(:,i,l)./G_spec_mu(:,i,l);
for j=1:size(H_spec1,1)
XX=real(H_spec1(j,:));
YY=real(D_spec1(j,:));
ZZ=real(Z_spec1(j,:));
XY_mat=[XX;YY];
ZZ_mat=(ZZ');
AB=(inv(XY_mat*XY_mat'))*(XY_mat*ZZ_mat);
azim_amp(j,i,l)=sqrt(AB(1)^2+AB(2)^2);
azim_theta1=atan2d(AB(2),AB(1));
if azim_theta1<0 azim_theta1=360+azim_theta1; end
azim_theta(j,i,l)=azim_theta1;
end
end
end
%% Identifying disturbed days
geomag_day1=find(datenum(index_geomag(:,1),1,index_geomag(:,2))==datadatenum_start);
for l=1:numel(LT_start)
geomag_day=geomag_day1(t_start(l)); %+1 hour backward
k=1;
for i=geomag_day:24:length(index_geomag)
ap(:,k,l)=index_geomag(i:i+3,6); %+1 hour onward
Dst(:,k,l)=index_geomag(i:i+3,5);
k=k+1;
if k>days_num break; end
end
end
ZG_quiet=ZG;
for l=1:numel(LT_start)
for i=1:days_num
if any(ap(:,i,l)>50) || any(Dst(:,i,l)<-50)
ZG_quiet(:,i,l)=deal(NaN);
end
end
end
if all(all(isnan(ZG_quiet)))
disp('No data available prior to the earthquake(s). Skipping');
pause(0.5);
continue;
end
%% Identifying precursors
for a=1:size(EQ_selsel,1)
for b=1:24
EQ_foundpre{a,b}='N/A';
end
end
days_backwards=[30,45,60];
for n=1:size(EQ_selsel,1)
time_now=datetime('now','Format','dd-MM-yyyy HH:mm');
if 0.025*EQ_selsel(n,2)<EQ_selsel(n,3)-4.5 EQ_dtctblty='Yes';
else EQ_dtctblty='No'; end
EQ_foundpre{n,1}=char(time_now);
EQ_foundpre{n,2}=sprintf('%s: %d %d %d)',stn,year_vec);
EQ_foundpre{n,3}=sprintf('%s',region);
EQ_foundpre{n,4}=[];
EQ_foundpre{n,5}=sprintf('%s',datetime(EQ_selsel(n,1),'ConvertFrom','datenum','Format','dd-MM-yyyy HH:mm:ss'));
EQ_foundpre{n,6}=sprintf('%.1f',EQ_selsel(n,3));
EQ_foundpre{n,7}=sprintf('%.0f',EQ_selsel(n,5));
EQ_foundpre{n,8}=sprintf('%.0f',EQ_selsel(n,2));
EQ_foundpre{n,9}=sprintf('%.2f',EQ_selsel(n,4));
EQ_foundpre{n,10}=sprintf('%s',EQ_dtctblty);
EQ_foundpre{n,11}=sprintf('%.2f',EQ_selsel(n,8));
EQ_foundpre{n,12}=sprintf('%.2f',EQ_selsel(n,6));
EQ_foundpre{n,13}=sprintf('%.2f',EQ_selsel(n,7));
EQ_foundpre{n,14}=[];
for f=1:numel(days_backwards)
days_bckwrd=days_backwards(f);
ZG_flex=ZG_quiet;
EQ_dateidx=find(floor(EQ_selsel(n,1))==datenum_vec);
foundpre=0;
days_range=EQ_dateidx:-1:EQ_dateidx-days_bckwrd;
for m=1:10
p=0;
clearvars max_ZG max_ZGidx
for o=EQ_dateidx:-1:EQ_dateidx-days_bckwrd
p=p+1;
max_ZG(p)=max(max(ZG_flex(:,o,:)));
max_ZGlinidx=find(ZG_flex(:,o,:)==max_ZG(p));
mat_dim=[size(ZG_flex,1),size(ZG_flex,3)];
if ~isempty(max_ZGlinidx)
max_ZGlinidx=max_ZGlinidx(1);
[max_ZGidx(1,p),max_ZGidx(2,p)]=ind2sub(mat_dim,max_ZGlinidx);
else
max_ZGidx(1:2,p)=[NaN,NaN]; end
end
max_ZG_flex=max_ZG;
for q=1:size(max_ZG,2)
[r,s]=max(max_ZG_flex);
if isnan(r) continue; end
azim_ZG=azim_theta(max_ZGidx(1,s),days_range(s),max_ZGidx(2,s));
azim_EQ=EQ_selsel(n,8);
diff_angle=azim_ZG-azim_EQ;
if diff_angle<-180 diff_angle=diff_angle+360;
elseif diff_angle>180 diff_angle=diff_angle-360; end
if abs(diff_angle)<=20
EQ_foundpre{n,15}=sprintf('%s',days_vec(days_range(s)));
EQ_foundpre{n,16}=sprintf('%02d - %02d',LT_start(max_ZGidx(2,s)),LT_end(max_ZGidx(2,s)));
EQ_foundpre{n,17}=sprintf('%.4f',r);
EQ_foundpre{n,18}=sprintf('%.4f',Z_spec_mu(max_ZGidx(1,s),days_range(s),max_ZGidx(2,s)));
EQ_foundpre{n,19}=sprintf('%.4f',G_spec_mu(max_ZGidx(1,s),days_range(s),max_ZGidx(2,s)));
EQ_foundpre{n,20}=sprintf('%d',floor(EQ_selsel(n,1))-datenum_vec(days_range(s)));
EQ_foundpre{n,21}=sprintf('%.4f',round(F_spec1(max_ZGidx(1,s)),4));
EQ_foundpre{n,22}=sprintf('%.2f',azim_ZG);
EQ_foundpre{n,23}=sprintf('%.2f',diff_angle);
EQ_foundpre{n,24}=sprintf('%d',m);
foundpre=1;
break;
else
max_ZG_flex(s)=NaN;
if all(isnan(max_ZG_flex))
break;
end
end
end
if foundpre==1
break;
else
for x=1:length(days_range)
if isnan(max_ZGidx(1,x)) continue; end
ZG_flex(max_ZGidx(1,x),days_range(x),max_ZGidx(2,x))=NaN;
end
end
end
if foundpre==1 break; end
end
end
%% Writing to xls file
xlsfilename='D:\Study\Record of appearance of earthquakes geomagnetic precursor.xlsx';
xlssheetname='Adib_14g';
[readxcel1,readxcel2,readxcel]=xlsread(xlsfilename,xlssheetname);
empcell=size(readxcel,1)+1;
xlsrange=strcat('A',string(empcell),':X',string(empcell+size(EQ_foundpre,1)-1));
xlswrite(xlsfilename,EQ_foundpre,xlssheetname,xlsrange)
disp(sprintf('Records made. Analysis on %s%d has completed.',stn,year));
%% Clearing variables
no_records=no_records+size(EQ_foundpre,1);
clearvars -except mag_min dis_max depth_max LT_start LT_end stn_num year stn_vec stn_MAGDAS station_vec index_geomag EQ_WORLD no_records
pause(0.5);
clc;
end
end
disp(sprintf('Analysis ends. %d of earthquakes recorded.',no_records));