How to set the time integration parameter when there are multiple viscoelastic layers with different Maxwell time

[ranneylxr]

Hi all,
In the guidebook, the integration time seems to be equal to year/tm, where year is what user wants. My question is: when there are multiple viscoelastic layers with different Maxwell time, which tm should be used to calculate the integration time?
For example, there is a jelly sandwich model where the tm of the lower curst is tm=10yr and the tm of the asthenosphere is tm=5yr. Then I want to calculate the post-seismic deformation after 70yr, how do I calculate the integration time? Should it be 70/5 or 70/10?
I am confused by this for a long time. Thank you very much!

[sbarbot]

The integration time is independent of viscosity. If the integration time is 70 years, just use an integration time of 70, assuming the time units is year. The viscosity structure simply controls how many relaxation times 70 years represent. With a Maxwell relaxation time of 10 years in the lower crust and 5 years in the asthenosphere, an integration time of 70 years will represent 7 Maxwell relaxation times in the lower crust and 14 Maxwell relaxation times in the asthenosphere. The code by default chooses time steps that are a fraction of the shortest relaxation times. However, the time step does not affect the total integration time. If the viscosity is low, many time steps are required to attain the total integration time. Best wishes, Sylvain

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________________________________ From: ranneylxr ***@***.***> Sent: Friday, June 7, 2024 6:30:30 PM To: geodynamics/relax ***@***.***> Cc: Subscribed ***@***.***> Subject: [geodynamics/relax] How to set the time integration parameter when there are multiple viscoelastic layers with different Maxwell time (Issue #10) Hi all, In the guidebook, the integration time seems to be equal to year/tm, where year is what user wants. My question is: when there are multiple viscoelastic layers with different Maxwell time, which tm should be used to calculate the integration time? For example, there is a jelly sandwich model where the tm of the lower curst is tm=10yr and the tm of the asthenosphere is tm=5yr. Then I want to calculate the post-seismic deformation after 70yr, how do I calculate the integration time? Should it be 70/5 or 70/10? I am confused by this for a long time. Thank you very much! — Reply to this email directly, view it on GitHub<https://urldefense.com/v3/__https://github.com/geodynamics/relax/issues/10__;!!LIr3w8kk_Xxm!oJhHPwOotkFinqi3wKV3VHANNo6zjl4PWJJZxvU3AcAsP_lAqwJ_MkWV-Ke6JZF6vuR_V52MLKFj9kw5QCJ4b5E$>, or unsubscribe<https://urldefense.com/v3/__https://github.com/notifications/unsubscribe-auth/ABJHTWC7AMGVW6QKNXR6PATZGJNDNAVCNFSM6AAAAABI7RIAIOVHI2DSMVQWIX3LMV43ASLTON2WKOZSGM2DCMZUGYYDEMQ__;!!LIr3w8kk_Xxm!oJhHPwOotkFinqi3wKV3VHANNo6zjl4PWJJZxvU3AcAsP_lAqwJ_MkWV-Ke6JZF6vuR_V52MLKFj9kw5Ode5940$>. You are receiving this because you are subscribed to this thread.Message ID: ***@***.***>

[ranneylxr]

Hi Sylvain,
Thank you very much for your detail explanation! It helps a lot!
Best regards,
Xiaoran.