Amplitude Check

Investigate daily average (noise) amplitudes at a given frequency for every data channel. The daily average is corrected (levelled) by the median of average values of all stations. These levelled daily average values stay normally within a certain range. Unusual deviations of this value detected in a long term statistics indicate problems with data or metadata. The following table shows automatically detected deviations for three channels (ZNE or Z12), if existing, in color codes: green - OK, yellow - the last day shows unusual deviation, orange - the last week shows unusual deviation, red - the last month shows unusual deviation, gray or white - no (recent) data. The station set is separated in broadband stations (VBB) and short period (SP) stations, investigated at different frequencies. VBB stations show low scatter in the noise data at 0.15 Hz since the signal is dominated by the ocean microseism. For SP stations this frequency is out of scale. Therefore a higher frequency is chosen where the scatter is much larger and the resolution for detecting errors is reduced.

The figures below the table show the individual measurements on the channels. Description see there.

This page is daily updated.

last 365 days, created 25-Feb-2021

VBB Stations @ 0.15Hz
GR.ASSE GR.BFO GR.BRG GR.BSEG
GR.BUG GR.CLL GR.CLZ GR.FBRG
GR.FUR GR.GEC2 GR.GEC7 GR.GOLD
GR.GOR1 GR.GRA1 GR.GRA2 GR.GRA3
GR.GRA4 GR.GRB1 GR.GRB2 GR.GRB3
GR.GRB4 GR.GRB5 GR.GRC1 GR.GRC2
GR.GRC3 GR.GRC4 GR.GTTG GR.HAM4
GR.HLGA1 GR.HLGA3 GR.HLGB1 GR.HLGB2
GR.IGAD GR.KAST GR.KHUS GR.KUDEN
GR.LNIZ GR.LUEB GR.MILB GR.MOX
GR.RETH GR.RETHO GR.SKMB GR.TNS
GR.UBR GR.WET GR.ZARR SX.NEUB
SX.TANN SX.WIMM TH.ABG1 TH.ANNA
TH.BBWF TH.BONN TH.CHRS TH.CRUX
TH.FRAU TH.GEIDO TH.GRZ1 TH.HKWD
TH.HWTS TH.LEIB1 TH.MEHR TH.MLFH
TH.MODW TH.MORAS TH.NEUST TH.PLN
TH.POSS TH.RANIS TH.SONN TH.SPAHL
TH.ZEITZ TH.ZEU

SP Stations @ 1.00Hz
GR.A807 GR.DEEL GR.FAHL GR.GEA0
GR.GEA1 GR.GEA2 GR.GEA3 GR.GEB1
GR.GEB2 GR.GEB3 GR.GEB4 GR.GEB5
GR.GEC1 GR.GEC3 GR.GEC4 GR.GEC5
GR.GEC6 GR.GED1 GR.GED2 GR.GED3
GR.GED4 GR.GED5 GR.GED6 GR.GED7
GR.GED8 GR.GED9 GR.INS1 GR.INS3
GR.INS5 GR.INS6B GR.INS7 GR.INS8
GR.RAST GR.SEVE GR.SYKE GR.TMO20
GR.TMO22 GR.TMO54 GR.TMO55 GR.TMO57
GR.TMO66 GR.UNDO RN.BAVN RN.BKLB
RN.BTEZ RN.BULI RN.HMES RN.IBBE
RN.IBBS RN.ZER1 RN.ZERL SX.FBE
SX.GUNZ SX.MULD SX.SCHF SX.TRIB
SX.WERD SX.WERN

Colors: no data amplitude ok last day over thresh last week over thresh last month over thresh


The figures below show the levelled average of the last 365 days (x-axis: 0 = one year ago, 364 = yesterday) in color codes, scaled by the individual standard deviation of the measurement series. Bold colors in red and blue indicate large deviations from the average to high or low values, respectively. Gray or pastel shaded colors represent the normal scatter. White means no data computed. The numbers after 'm:' and 's:' in the figure titles are the relative mean and the standard deviation in log10(nm/s), respectively. Please note that the mean and standard deviation is computed after removing the upper and lower 15% of the data to remove the influence of outliers. Maximum color boldness is reached at 10 standard deviations (red for positive, blue for negative amplitudes). The color intensity for log amplitudes below 5.5 standard deviations is reduced by a square function. Similar color patterns at neighbored stations indicate natural undulations in the noise signal.

Color coded deviations VBB

relative amplitudes VBB


Color coded deviations SP

relative amplitudes SP