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Satoshi Fujiwara
Geospatial Information Authority of Japan
Corresponding Author
ORCiD: https://orcid.org/0000-0002-7541-9266
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Postseismic deformation continues for a long duration after major earthquakes. A previous study has shown that temporal changes in postseismic deformation can be approximated through simple functions. Almost 10 years have passed since the 2011 M9 Tohoku-Oki earthquake, and data at continuously operating global navigation satellite system stations have accumulated. We performed statistical processing of the data on postseismic deformations of this earthquake and obtained and verified their spatiotemporal distribution. We were able to approximate the postseismic deformations over a wide area with a standard deviation of 1 cm for approximately 10 years using two logarithmic and one exponential functions. However, the residuals from the functional model showed a sharp deviation from 2015. Although the pattern of postseismic deformation did not change after the earthquake, a change in steady-state velocity occurred from 2015 and continues till date. By improving the functional model to incorporate this steady-state velocity, we can reduce the overall standard deviation of the residuals of more than 200 stations distributed over more than 1000 km to less than 0.4 cm in the horizontal component. Furthermore, the spatial distributions of the coefficients of each time constant are not random and have a natural spread, which makes it possible to grid model them in terms of a spatial function. The spatial distributions of the short- and long-period components of the functional model and the afterslip and viscoelastic relaxation calculated by a physical model are similar to each other, respectively. Each time function has a meaning related to the physical processes in the underground, which provides an understanding of the physical phenomena involved in seismogenesis.
Keywords
2011 Tohoku-Oki earthquake, crustal deformation, postseismic deformation, slip, global navigation satellite system time series, predicting model
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This is a list of supplementary files associated with this preprint. Click to download.
- GraphicalabstractFujiwara202104.png
- SupplementaryfiguresFujiwara202104.pdf
Additional files Fig. S1 Difference in fitting period and difference in physical model a 2.0-year fitting of the short-period logarithmic term, b 3.9-year fitting of the short-period logarithmic term, c a minus b. d Viscoelastic relaxation component of the physical model minus long-period logarithmic and exponential terms of the functional model. The values for each term are three years after the earthquake (March 11, 2014) when the values immediately after the earthquake were set to zero. The physical model was obtained from Suito (2017). Fig. S2 Observed and predicted postseismic deformation using the functional model At the four stations of a Minase, b Miyako, c Yamoto, and d Choshi (shown in Fig. 1). The three components of EW, NS, and UD were drawn for each station from the day after the earthquake to 2026.5. The black dots represent daily observations. The four broken lines are the time series of predicted values for each fitting period (2.0, 3.9, 5.8, and 8.9-year). Fig. S3 Observed and predicted postseismic deformation At the four stations of a Minase, b Miyako, c Yamoto, and d Choshi (shown in Fig. 1). The three components of EW, NS, and UD were drawn for each station from the day after the earthquake to 2026.5. Gray dots are daily observations used for the 3.9-year fitting. The black dots represent daily observations during the prediction period. The red lines are the predicted values based on Eq. (3) and the other lines are the terms in Eq. (3) (see text).
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CURRENT STATUS: Under Revision
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Posted 13 Sep, 2021
Reviewer #2 agreed
On 13 Sep, 2021
Review #2 received
Received 13 Sep, 2021
Review #1 received
Received 05 Sep, 2021
Reviews received
Received 19 Aug, 2021
Reviewer #1 agreed
On 18 Aug, 2021
Reviewers invited
Invitations sent on 11 Aug, 2021
Editor assigned
On 28 Jul, 2021
Submission checks complete
On 28 Jul, 2021
Editor invited
On 28 Jul, 2021
First submitted
On 28 Jul, 2021
Editorial decision: Minor Revision
On 01 Jun, 2021
This version was not preprinted
Version 1
Posted 21 Apr, 2021
No community comments so far
Editorial decision: Major Revision
On 31 May, 2021
Review #2 received
Received 26 May, 2021
Review #1 received
Received 14 May, 2021
Reviewer #2 agreed
On 25 Apr, 2021
Reviewer #1 agreed
On 23 Apr, 2021
Reviewers invited
Invitations sent on 20 Apr, 2021
Editor assigned
On 15 Apr, 2021
Submission checks complete
On 15 Apr, 2021
Editor invited
On 15 Apr, 2021
First submitted
On 13 Apr, 2021
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Subject Areas
Planetary Geology
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This preprint is under consideration at Earth, Planets and Space. A preprint is a preliminary version of a manuscript that has not completed peer review at a journal. Research Square does not conduct peer review prior to posting preprints. The posting of a preprint on this server should not be interpreted as an endorsement of its validity or suitability for dissemination as established information or for guiding clinical practice.
Learn more about In Review
Full paper
Satoshi Fujiwara
Geospatial Information Authority of Japan
Corresponding Author
ORCiD: https://orcid.org/0000-0002-7541-9266
Badges
Prescreen
This manuscript passed our Prescreen assessment
Complete author information
Appropriate declaration statements
Potential risks to human health
Prescreen
Peer Review Timeline
CURRENT STATUS: Under Revision
Version (no preprint)
Posted 13 Sep, 2021
Reviewer #2 agreed
On 13 Sep, 2021
Review #2 received
Received 13 Sep, 2021
Review #1 received
Received 05 Sep, 2021
Reviews received
Received 19 Aug, 2021
Reviewer #1 agreed
On 18 Aug, 2021
Reviewers invited
Invitations sent on 11 Aug, 2021
Editor assigned
On 28 Jul, 2021
Submission checks complete
On 28 Jul, 2021
Editor invited
On 28 Jul, 2021
First submitted
On 28 Jul, 2021
Editorial decision: Minor Revision
On 01 Jun, 2021
This version was not preprinted
Version 1
Posted 21 Apr, 2021
No community comments so far
Editorial decision: Major Revision
On 31 May, 2021
Review #2 received
Received 26 May, 2021
Review #1 received
Received 14 May, 2021
Reviewer #2 agreed
On 25 Apr, 2021
Reviewer #1 agreed
On 23 Apr, 2021
Reviewers invited
Invitations sent on 20 Apr, 2021
Editor assigned
On 15 Apr, 2021
Submission checks complete
On 15 Apr, 2021
Editor invited
On 15 Apr, 2021
First submitted
On 13 Apr, 2021
Metrics
Comments: 0
PDF Downloads: ...
HTML Views: ...
Subject Areas
Planetary Geology
License:
This work is licensed under a CC BY 4.0 License. Read Full License
Postseismic deformation continues for a long duration after major earthquakes. A previous study has shown that temporal changes in postseismic deformation can be approximated through simple functions. Almost 10 years have passed since the 2011 M9 Tohoku-Oki earthquake, and data at continuously operating global navigation satellite system stations have accumulated. We performed statistical processing of the data on postseismic deformations of this earthquake and obtained and verified their spatiotemporal distribution. We were able to approximate the postseismic deformations over a wide area with a standard deviation of 1 cm for approximately 10 years using two logarithmic and one exponential functions. However, the residuals from the functional model showed a sharp deviation from 2015. Although the pattern of postseismic deformation did not change after the earthquake, a change in steady-state velocity occurred from 2015 and continues till date. By improving the functional model to incorporate this steady-state velocity, we can reduce the overall standard deviation of the residuals of more than 200 stations distributed over more than 1000 km to less than 0.4 cm in the horizontal component. Furthermore, the spatial distributions of the coefficients of each time constant are not random and have a natural spread, which makes it possible to grid model them in terms of a spatial function. The spatial distributions of the short- and long-period components of the functional model and the afterslip and viscoelastic relaxation calculated by a physical model are similar to each other, respectively. Each time function has a meaning related to the physical processes in the underground, which provides an understanding of the physical phenomena involved in seismogenesis.
Figure 1
Figure 2
Figure 3
Figure 4
Figure 5
Figure 6
Figure 7
Figure 8
Figure 9
Figure 10
Figure 11
Figure 12
This is a list of supplementary files associated with this preprint. Click to download.
- GraphicalabstractFujiwara202104.png
- SupplementaryfiguresFujiwara202104.pdf
Additional files Fig. S1 Difference in fitting period and difference in physical model a 2.0-year fitting of the short-period logarithmic term, b 3.9-year fitting of the short-period logarithmic term, c a minus b. d Viscoelastic relaxation component of the physical model minus long-period logarithmic and exponential terms of the functional model. The values for each term are three years after the earthquake (March 11, 2014) when the values immediately after the earthquake were set to zero. The physical model was obtained from Suito (2017). Fig. S2 Observed and predicted postseismic deformation using the functional model At the four stations of a Minase, b Miyako, c Yamoto, and d Choshi (shown in Fig. 1). The three components of EW, NS, and UD were drawn for each station from the day after the earthquake to 2026.5. The black dots represent daily observations. The four broken lines are the time series of predicted values for each fitting period (2.0, 3.9, 5.8, and 8.9-year). Fig. S3 Observed and predicted postseismic deformation At the four stations of a Minase, b Miyako, c Yamoto, and d Choshi (shown in Fig. 1). The three components of EW, NS, and UD were drawn for each station from the day after the earthquake to 2026.5. Gray dots are daily observations used for the 3.9-year fitting. The black dots represent daily observations during the prediction period. The red lines are the predicted values based on Eq. (3) and the other lines are the terms in Eq. (3) (see text).
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