# Assigning Plate ID to non-present day raster

**URL:** <https://discourse.gplates.org/t/assigning-plate-id-to-non-present-day-raster/766>\
**Category:** Q&A\
**Created:** [6 November 2023 13:08 UTC](https://discourse.gplates.org/t/assigning-plate-id-to-non-present-day-raster/766 "2023-11-06T13:08:41Z")\
**Posts on this page:** 3\
**Page:** 1

<div class="post-metadata">

**Author:** ![Les](https://discourse.gplates.org/letter_avatar_proxy/v4/letter/l/db5fbb/32.png) [@Les](https://discourse.gplates.org/u/Les)\
**Post date:** [6 November 2023 13:08 UTC](https://discourse.gplates.org/t/assigning-plate-id-to-non-present-day-raster/766/1 "2023-11-06T13:08:41Z")

</div>

Hi  
I have a raster representing parameters at 79Ma. I wanted to use GPlates to rotate these to present-day.  
I have used Assign Plate ID to cookie cut the raster, assigning current construction time 79Ma.  
However, when I assign the plate polygons to the raster, the raster seems to be cut using the plate polygons in their present-day configuration, following which raster is rotated back to 79Ma.  
Is there a way to rotate a “paleo”-raster to present-day within GPlates (2.3)?

---

<div class="post-metadata">

**Author:** ![john.cannon](https://discourse.gplates.org/letter_avatar_proxy/v4/letter/j/3e96dc/32.png) [@john.cannon](https://discourse.gplates.org/u/john.cannon)\
**Post date:** [7 November 2023 02:22 UTC](https://discourse.gplates.org/t/assigning-plate-id-to-non-present-day-raster/766/2 "2023-11-07T02:22:59Z")

</div>

Currently, in GPlates, the raster must be a _present-day_ raster in that the raster data must represent present-day positions. The raster can also be time-dependent but the data in each time slice is still expected to represent present-day positions (ie, be in the plate reference frame where the plates don’t move/reconstruct through time) - GPlates will then reconstruct the plates and the raster data will follow the plate motion.

To reconstruct a raster representing data at **non-zero** times you can use _gplately_ with a non-zero `time` in the [Raster](https://gplates.github.io/gplately/grids.html#gplately.grids.Raster) object (see [here](https://github.com/GPlates/gplately#the-raster-object)). There’s also a Notebook covering rasters [here](https://github.com/GPlates/gplately/blob/master/Notebooks/06-Rasters.ipynb).

---

<div class="post-metadata">

**Author:** ![Les](https://discourse.gplates.org/letter_avatar_proxy/v4/letter/l/db5fbb/32.png) [@Les](https://discourse.gplates.org/u/Les)\
**Post date:** [7 November 2023 07:03 UTC](https://discourse.gplates.org/t/assigning-plate-id-to-non-present-day-raster/766/3 "2023-11-07T07:03:20Z")

</div>

Thanks, I’ll give that a try.