Update 09-CreatingMotionPathsAndFlowlines.ipynb in accordance with suggestions from M.S.

[michaelchin]

1. The motion path for Hawaii on this page is wrong (see the image with the title “Motion path if the Hawaiian-Emperor Chain”.
   The motion path needs to follow the Hawaiian-Emperor seamount chain (i.e. it is meant to go in the opposite direction).

2. Get rid of the India-Eurasia example of motion paths

3. the y-axis of rate of motion starts at 0 so that people can see that there is no motion after 55 Ma (in the 2nd flowline example).

[jcannon-gplates]

Thanks for fixing that Michael. I must've accidentally swapped the motion path plate IDs.

I guess @mariaseton wanted the India-Eurasia example removed. However it was the only place that demonstrated how to reconstruct motion paths to a past time (as in, display the motion path at a non-present day time), and also how to create a motion path using reconstructed seed point locations (ie, not present day locations). This pretty much mirrored what is done in the flowline example.

We could transfer that to the Hawaiian-Emporer chain example, but probably easier to just reinstate the India-Eurasia example, unless there was something wrong with it?

[michaelchin]

I am neutral about the India-Eurasia example . Either way is fine with me. Maybe we can discuss it in the next auscope meeting.

And it seems the plate IDs were swapped in this commit 6d23c94#diff-976c8bd4e54291644eb014f0440b4699ce8fcd2d7658450000e8df6b118b4ec6

[jcannon-gplates]

I am neutral about the India-Eurasia example . Either way is fine with me. Maybe we can discuss it in the next auscope meeting.

Sounds good. And I'll reply to Maria (in the email you just forwarded).

And it seems the plate IDs were swapped in this commit 6d23c94

And then I think you fixed that in 5cac924.

And then I got confused because the moving plate ID was 901 and anchor plate ID was 2 in example 09-CreatingMotionPathsAndFlowlines. Those plate IDs have always been that way, and the example has always treated the anchor plate ID as the motion path's reconstruction plate ID, and the moving plate as the motion path's relative plate. But that confused me and I thought it must've been wrong, so I essentially changed the example to make the moving plate ID the motion path's reconstruction plate (in #355). But that was a mistake, and made the motion path go in the opposite direction. And you just now fixed this in 45459a0, by making 2 the moving plate and 901 the anchor plate (ie, swapped) which makes more sense.

So now we have a record of what went wrong 😅

[michaelchin]

yes, those plate IDs also confused me. I made the change based on the gplates tutorial ftp://ftp.earthbyte.org/earthbyte/GPlates/TutorialData_GPlates2.1/Tutorial_2.3_Flowlines_and_Motion_Paths.pdf.

[michaelchin]

but in this version of the tutorial

https://docs.google.com/document/d/1m663luFqCDTbREDaG8DpLmay_kKIzS7b7x7RjqkGTkc/pub#h.e21dba939bd9

the moving plate ID is 0, which makes it more confusing...

[jcannon-gplates]

I made the change based on the gplates tutorial

Ah, good call!

Yeah, moving plate 0 would be confusing (not actually a hotspot).