[CIG-SHORT] RELAX Question

[Sylvain Barbot]

Hi Austin,

The Tibet lakes have a great loading signal. You can use Relax to
simulate the deformation, but you need to be careful about how
important the elastic stratification is. If your data are close to the
source, you're fine. I presume you are using paleo-shoreline data. If
so, use the shallow rigidity for the entire domain. If you are
modeling far-field data, you should use a code that have a layered
elastic structure, i.e., (Farrell, 1972).

The example attached models the deformation from the Indian monsoon
using Grace data. The example cycleload.sh creates a periodic surface
load.

Best wishes,
Sylvain



On Tue, Jan 19, 2016 at 10:51 AM, Austin Madson <amadson at ucla.edu> wrote:
> Professor Barbot,
>
> Thanks for the prompt response. I looked at the documentation and the man
> page (as well as the examples on the PDF on the geodynamics website) and
> have made progress.
>
> As an fyi, we plan on modeling several hundred years of surface loading from
> very large lakes (i.e. time dependent loads). Are there any RELAX surface
> load examples laying around (they can just be single/multiple point and even
> instantaneous (no time function)? The GRACE example on the example pdf
> "hides" the data in various dat files (which makes sense if you're using a
> lot of data, but it's hard to see their example inputs).
>
> I expect to see only millimeters of deformation throughout the run - will
> the outputs be precise enough if I use the correct SI units throughout?
>
> Cheers,
> Austin Madson
>
> On Sun, Jan 17, 2016 at 4:06 PM, Sylvain Barbot <sylbar.vainbot at gmail.com>
> wrote:
>>
>> Hi Austin,
>>
>> The details of the input file for surface loads are in the documentation
>> and in the man page. There are some pdf files on the geodynamics website
>> that show examples of surface loads for the Himalayan region if I recall
>> well.
>>
>> But the input file simply expects a list of squares with their associated
>> traction. So depending on your project, this can be a single point, say to
>> represent the loading of a dam, or a complicated function of space and time.
>> If your change of load is instantaneous, you need only one event. Of your
>> load is time dependent, you need as many events as you have time steps. I
>> can be more specific, but I need more information about your practical
>> goals.
>>
>> Cheers,
>> Sylvain
>>
>>
>> On Monday, January 18, 2016, Austin Madson <amadson at ucla.edu> wrote:
>>>
>>> Professor Barbot,
>>>
>>> I have a quick question re: RELAX - Is there any more information out
>>> there with respect to utilizing RELAX for deformation responses to surface
>>> loading? I have looked through all of the examples as well as the
>>> slides/tutorials on the geodynamics.org website.
>>>
>>> Can you provide any further information? Or can you point me in a better
>>> direction?
>>>
>>> Cheers,
>>> Austin Madson
>
>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: load1.sh
Type: application/x-sh
Size: 1800 bytes
Desc: not available
URL: <http://lists.geodynamics.org/pipermail/cig-short/attachments/20160120/487b82a6/attachment-0002.sh>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: 20020828_20020906_km.xyz
Type: chemical/x-pdb
Size: 27929 bytes
Desc: not available
URL: <http://lists.geodynamics.org/pipermail/cig-short/attachments/20160120/487b82a6/attachment-0001.pdb>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: cycleload.sh
Type: application/x-sh
Size: 1467 bytes
Desc: not available
URL: <http://lists.geodynamics.org/pipermail/cig-short/attachments/20160120/487b82a6/attachment-0003.sh>