From ben.mather at sydney.edu.au Sun Dec 16 11:22:39 2018 From: ben.mather at sydney.edu.au (Ben Mather) Date: Sun, 16 Dec 2018 00:22:39 +0000 Subject: [GPlates-discuss] Reconstruct rasters with pyGPlates Message-ID: Hi team! I was wondering if it is possible to reconstruct raster images back in time like it is in regular GPlates? It would be very useful to, say, have a 2D numpy array that could be deformed with respect to a rotation model. Cheers, Ben Dr. Ben Mather | Computational Geophysicist Room 418, Madsen Building F09 School of Geoscience, Faculty of Science The University of Sydney, NSW 2006 m +61 422 470 117 w benmather.info t twitter.com/BenRMather -------------- next part -------------- An HTML attachment was scrubbed... URL: From mark.brandon at yale.edu Mon Dec 17 01:41:37 2018 From: mark.brandon at yale.edu (Mark Brandon) Date: Sun, 16 Dec 2018 09:41:37 -0500 Subject: [GPlates-discuss] importing seed points In-Reply-To: References: Message-ID: <94972678-32A3-4E89-9362-A1FFA499E45F@yale.edu> I am trying to import a list of seed points for the flow line calculation. I have successfully used of opening a gmt file (lon\tlat\r format, line by line) and that shows up in the list of loaded feature collections. (One can also paste the gmt file into the application with the same result.) But it is not clear to me how to convert this feature into a collection of seed points for the flow line calculation. Best, Mark From chhei at paleoearthlabs.org Mon Dec 17 06:00:47 2018 From: chhei at paleoearthlabs.org (Christian Heine) Date: Sun, 16 Dec 2018 20:00:47 +0100 Subject: [GPlates-discuss] importing seed points In-Reply-To: <94972678-32A3-4E89-9362-A1FFA499E45F@yale.edu> References: <94972678-32A3-4E89-9362-A1FFA499E45F@yale.edu> Message-ID: <0E0AD30D-AB36-40DE-ABF4-B503A906C56B@paleoearthlabs.org> Hi Mark, Flowlines/seed points are a special kind of a beast - AFAIK you cannot save them in an OGR-type format (SHP, GMT etc) as come with a few special properties which are only available in GMPl (GPlates Markup Language). This is mainly because of the attached time sequence (gpml:times property) is a nested property which is not a trivial feat in the standard GIS format. Unless I am not mistaken, you'd have the following options : 1) Change the points individually in GPlates - that might be the best way if you have not too many points: Change the initial feature type mapping by selecting the point(s) in question, then ctrl+e to edit, change "feature type" (first line in the window that pops up) to "Flowline" and add a new property (click on 'add property' select gpml:times and adjust as needed) 2) Programmatically/manually wrap your point data in the correct GPML syntax for a flowline seed points using a text editor/script. A simple example with one point is attached. It is relatively straightforward but make sure to not break the XML. 3) A pyGPlates route would be to simply feed your point geometries to construct a flowline feature: https://protect-au.mimecast.com/s/zIjaC3Q8Z2F41w9qHgC9Me?domain=gplates.org The latter being potentially the fastest way to do this for a larger number of features. HTH, Christian -------------- next part -------------- A non-text attachment was scrubbed... Name: test_flow.gpml Type: application/octet-stream Size: 9719 bytes Desc: not available URL: -------------- next part -------------- > On 16 Dec 2018, at 15:41, Mark Brandon wrote: > > I am trying to import a list of seed points for the flow line calculation. I have successfully used of opening a gmt file (lon\tlat\r format, line by line) and that shows up in the list of loaded feature collections. (One can also paste the gmt file into the application with the same result.) But it is not clear to me how to convert this feature into a collection of seed points for the flow line calculation. > Best, > Mark > > _______________________________________________ > GPlates-discuss mailing list > GPlates-discuss at mailman.sydney.edu.au > https://mailman.sydney.edu.au/mailman/listinfo/gplates-discuss > -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 901 bytes Desc: Message signed with OpenPGP URL: From mark.brandon at yale.edu Mon Dec 17 06:35:16 2018 From: mark.brandon at yale.edu (Mark Brandon) Date: Sun, 16 Dec 2018 14:35:16 -0500 Subject: [GPlates-discuss] importing seed points In-Reply-To: <0E0AD30D-AB36-40DE-ABF4-B503A906C56B@paleoearthlabs.org> References: <94972678-32A3-4E89-9362-A1FFA499E45F@yale.edu> <0E0AD30D-AB36-40DE-ABF4-B503A906C56B@paleoearthlabs.org> Message-ID: <6EBA7C8F-D4D8-4DF6-A1BF-AE5A0ADD9340@yale.edu> Christian, Thanks for the back story. I found a different way to accomplish my objective. I am interested in constructing flow lines for various geometric features that already in the GPlates data set. Consider, for example, flow lines for the Juan de Fuca ridge. The approach that seems to work is to select the JdF ridge as a feature, and then to select Edit > Copy Geometry to Digitize Tool. The coordinates will be imported into the New Geometry window on the right. At that point, the "imported" geometry can be modified using the various digitize tools. To complete the important, select the New Multipoint Digitize Tool, and then select Create Feature below the New Geometry window on the right. You can select an appropriate feature option at that point. My my task, I select the Flow line option and continue from there... Best, Mark > On Dec 16, 2018, at 2:00 PM, Christian Heine wrote: > > Hi Mark, > > Flowlines/seed points are a special kind of a beast - AFAIK you cannot save them in an OGR-type format (SHP, GMT etc) as come with a few special properties which are only available in GMPl (GPlates Markup Language). This is mainly because of the attached time sequence (gpml:times property) is a nested property which is not a trivial feat in the standard GIS format. > > Unless I am not mistaken, you'd have the following options : > > 1) Change the points individually in GPlates - that might be the best way if you have not too many points: Change the initial feature type mapping by selecting the point(s) in question, then ctrl+e to edit, change "feature type" (first line in the window that pops up) to "Flowline" and add a new property (click on 'add property' select gpml:times and adjust as needed) > > 2) Programmatically/manually wrap your point data in the correct GPML syntax for a flowline seed points using a text editor/script. A simple example with one point is attached. It is relatively straightforward but make sure to not break the XML. > > 3) A pyGPlates route would be to simply feed your point geometries to construct a flowline feature: https://protect-au.mimecast.com/s/_1ZCCANZvPiRyv8zUG5S_l?domain=gplates.org > > The latter being potentially the fastest way to do this for a larger number of features. > > HTH, > Christian > > >> On 16 Dec 2018, at 15:41, Mark Brandon wrote: >> >> I am trying to import a list of seed points for the flow line calculation. I have successfully used of opening a gmt file (lon\tlat\r format, line by line) and that shows up in the list of loaded feature collections. (One can also paste the gmt file into the application with the same result.) But it is not clear to me how to convert this feature into a collection of seed points for the flow line calculation. >> Best, >> Mark >> >> _______________________________________________ >> GPlates-discuss mailing list >> GPlates-discuss at mailman.sydney.edu.au >> https://mailman.sydney.edu.au/mailman/listinfo/gplates-discuss >> > > _______________________________________________ > GPlates-discuss mailing list > GPlates-discuss at mailman.sydney.edu.au > https://mailman.sydney.edu.au/mailman/listinfo/gplates-discuss From chhei at paleoearthlabs.org Mon Dec 17 07:41:50 2018 From: chhei at paleoearthlabs.org (Christian Heine) Date: Sun, 16 Dec 2018 21:41:50 +0100 Subject: [GPlates-discuss] importing seed points In-Reply-To: <6EBA7C8F-D4D8-4DF6-A1BF-AE5A0ADD9340@yale.edu> References: <94972678-32A3-4E89-9362-A1FFA499E45F@yale.edu> <0E0AD30D-AB36-40DE-ABF4-B503A906C56B@paleoearthlabs.org> <6EBA7C8F-D4D8-4DF6-A1BF-AE5A0ADD9340@yale.edu> Message-ID: Hi Mark, > On 16 Dec 2018, at 20:35, Mark Brandon wrote: [...] > At that point, the "imported" geometry can be modified using the various digitize tools. To complete the important, select the New Multipoint Digitize Tool, and then select Create Feature below the New Geometry window on the right. You can select an appropriate feature option at that point. My my task, I select the Flow line option and continue from there... Yes that of course also works. I was under the impression that you wanted to create flowlines from new features. Make sure to save your flowlines as *.gpml files so that the flowline properties don't get lost. Cheers, Christian >> On Dec 16, 2018, at 2:00 PM, Christian Heine wrote: >> >> Hi Mark, >> >> Flowlines/seed points are a special kind of a beast - AFAIK you cannot save them in an OGR-type format (SHP, GMT etc) as come with a few special properties which are only available in GMPl (GPlates Markup Language). This is mainly because of the attached time sequence (gpml:times property) is a nested property which is not a trivial feat in the standard GIS format. >> >> Unless I am not mistaken, you'd have the following options : >> >> 1) Change the points individually in GPlates - that might be the best way if you have not too many points: Change the initial feature type mapping by selecting the point(s) in question, then ctrl+e to edit, change "feature type" (first line in the window that pops up) to "Flowline" and add a new property (click on 'add property' select gpml:times and adjust as needed) >> >> 2) Programmatically/manually wrap your point data in the correct GPML syntax for a flowline seed points using a text editor/script. A simple example with one point is attached. It is relatively straightforward but make sure to not break the XML. >> >> 3) A pyGPlates route would be to simply feed your point geometries to construct a flowline feature: https://protect-au.mimecast.com/s/wAuECVAGXPtZr8VrIG3yKh?domain=gplates.org >> >> The latter being potentially the fastest way to do this for a larger number of features. >> >> HTH, >> Christian >> >> >>> On 16 Dec 2018, at 15:41, Mark Brandon wrote: >>> >>> I am trying to import a list of seed points for the flow line calculation. I have successfully used of opening a gmt file (lon\tlat\r format, line by line) and that shows up in the list of loaded feature collections. (One can also paste the gmt file into the application with the same result.) But it is not clear to me how to convert this feature into a collection of seed points for the flow line calculation. >>> Best, >>> Mark >>> >>> _______________________________________________ >>> GPlates-discuss mailing list >>> GPlates-discuss at mailman.sydney.edu.au >>> https://mailman.sydney.edu.au/mailman/listinfo/gplates-discuss >>> >> >> _______________________________________________ >> GPlates-discuss mailing list >> GPlates-discuss at mailman.sydney.edu.au >> https://mailman.sydney.edu.au/mailman/listinfo/gplates-discuss > > _______________________________________________ > GPlates-discuss mailing list > GPlates-discuss at mailman.sydney.edu.au > https://mailman.sydney.edu.au/mailman/listinfo/gplates-discuss > -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 901 bytes Desc: Message signed with OpenPGP URL: From mark.brandon at yale.edu Mon Dec 17 07:45:32 2018 From: mark.brandon at yale.edu (Mark Brandon) Date: Sun, 16 Dec 2018 15:45:32 -0500 Subject: [GPlates-discuss] importing seed points In-Reply-To: References: <94972678-32A3-4E89-9362-A1FFA499E45F@yale.edu> <0E0AD30D-AB36-40DE-ABF4-B503A906C56B@paleoearthlabs.org> <6EBA7C8F-D4D8-4DF6-A1BF-AE5A0ADD9340@yale.edu> Message-ID: Christian, It might be worthwhile broadcasting the benefits of the "Copy to Dig" option. It is an awesome feature. There may be some documentation somewhere, but I have not found it yet. Best, Mark > On Dec 16, 2018, at 3:41 PM, Christian Heine wrote: > > Hi Mark, > >> On 16 Dec 2018, at 20:35, Mark Brandon wrote: > > [...] > >> At that point, the "imported" geometry can be modified using the various digitize tools. To complete the important, select the New Multipoint Digitize Tool, and then select Create Feature below the New Geometry window on the right. You can select an appropriate feature option at that point. My my task, I select the Flow line option and continue from there... > > Yes that of course also works. I was under the impression that you wanted to create flowlines from new features. > > Make sure to save your flowlines as *.gpml files so that the flowline properties don't get lost. > > Cheers, > Christian > > > > > > >>> On Dec 16, 2018, at 2:00 PM, Christian Heine wrote: >>> >>> Hi Mark, >>> >>> Flowlines/seed points are a special kind of a beast - AFAIK you cannot save them in an OGR-type format (SHP, GMT etc) as come with a few special properties which are only available in GMPl (GPlates Markup Language). This is mainly because of the attached time sequence (gpml:times property) is a nested property which is not a trivial feat in the standard GIS format. >>> >>> Unless I am not mistaken, you'd have the following options : >>> >>> 1) Change the points individually in GPlates - that might be the best way if you have not too many points: Change the initial feature type mapping by selecting the point(s) in question, then ctrl+e to edit, change "feature type" (first line in the window that pops up) to "Flowline" and add a new property (click on 'add property' select gpml:times and adjust as needed) >>> >>> 2) Programmatically/manually wrap your point data in the correct GPML syntax for a flowline seed points using a text editor/script. A simple example with one point is attached. It is relatively straightforward but make sure to not break the XML. >>> >>> 3) A pyGPlates route would be to simply feed your point geometries to construct a flowline feature: https://protect-au.mimecast.com/s/AUdpCYWL1vi9RXZVt0BdU0?domain=gplates.org >>> >>> The latter being potentially the fastest way to do this for a larger number of features. >>> >>> HTH, >>> Christian >>> >>> >>>> On 16 Dec 2018, at 15:41, Mark Brandon wrote: >>>> >>>> I am trying to import a list of seed points for the flow line calculation. I have successfully used of opening a gmt file (lon\tlat\r format, line by line) and that shows up in the list of loaded feature collections. (One can also paste the gmt file into the application with the same result.) But it is not clear to me how to convert this feature into a collection of seed points for the flow line calculation. >>>> Best, >>>> Mark >>>> >>>> _______________________________________________ >>>> GPlates-discuss mailing list >>>> GPlates-discuss at mailman.sydney.edu.au >>>> https://mailman.sydney.edu.au/mailman/listinfo/gplates-discuss >>>> >>> >>> _______________________________________________ >>> GPlates-discuss mailing list >>> GPlates-discuss at mailman.sydney.edu.au >>> https://mailman.sydney.edu.au/mailman/listinfo/gplates-discuss >> >> _______________________________________________ >> GPlates-discuss mailing list >> GPlates-discuss at mailman.sydney.edu.au >> https://mailman.sydney.edu.au/mailman/listinfo/gplates-discuss >> > > _______________________________________________ > GPlates-discuss mailing list > GPlates-discuss at mailman.sydney.edu.au > https://mailman.sydney.edu.au/mailman/listinfo/gplates-discuss From chhei at paleoearthlabs.org Mon Dec 17 09:07:34 2018 From: chhei at paleoearthlabs.org (Christian Heine) Date: Sun, 16 Dec 2018 23:07:34 +0100 Subject: [GPlates-discuss] importing seed points In-Reply-To: References: <94972678-32A3-4E89-9362-A1FFA499E45F@yale.edu> <0E0AD30D-AB36-40DE-ABF4-B503A906C56B@paleoearthlabs.org> <6EBA7C8F-D4D8-4DF6-A1BF-AE5A0ADD9340@yale.edu> Message-ID: Hi Mark, > On 16 Dec 2018, at 21:45, Mark Brandon wrote: > > Christian, > It might be worthwhile broadcasting the benefits of the "Copy to Dig" option. It is an awesome feature. As the mailing list archives are public it is now ;-) > There may be some documentation somewhere, but I have not found it yet. You're probably right - I don't think that this workflow is explicitly documented. @John/Michael - Maybe time for a GPlates Wiki for such things? Cheers, Christian >> On Dec 16, 2018, at 3:41 PM, Christian Heine wrote: >> >> Hi Mark, >> >>> On 16 Dec 2018, at 20:35, Mark Brandon wrote: >> >> [...] >> >>> At that point, the "imported" geometry can be modified using the various digitize tools. To complete the important, select the New Multipoint Digitize Tool, and then select Create Feature below the New Geometry window on the right. You can select an appropriate feature option at that point. My my task, I select the Flow line option and continue from there... >> >> Yes that of course also works. I was under the impression that you wanted to create flowlines from new features. >> >> Make sure to save your flowlines as *.gpml files so that the flowline properties don't get lost. >> >> Cheers, >> Christian >> >> >> >> >> >> >>>> On Dec 16, 2018, at 2:00 PM, Christian Heine wrote: >>>> >>>> Hi Mark, >>>> >>>> Flowlines/seed points are a special kind of a beast - AFAIK you cannot save them in an OGR-type format (SHP, GMT etc) as come with a few special properties which are only available in GMPl (GPlates Markup Language). This is mainly because of the attached time sequence (gpml:times property) is a nested property which is not a trivial feat in the standard GIS format. >>>> >>>> Unless I am not mistaken, you'd have the following options : >>>> >>>> 1) Change the points individually in GPlates - that might be the best way if you have not too many points: Change the initial feature type mapping by selecting the point(s) in question, then ctrl+e to edit, change "feature type" (first line in the window that pops up) to "Flowline" and add a new property (click on 'add property' select gpml:times and adjust as needed) >>>> >>>> 2) Programmatically/manually wrap your point data in the correct GPML syntax for a flowline seed points using a text editor/script. A simple example with one point is attached. It is relatively straightforward but make sure to not break the XML. >>>> >>>> 3) A pyGPlates route would be to simply feed your point geometries to construct a flowline feature: https://protect-au.mimecast.com/s/vgO8CXLKZoi9vrX0U6QVIh?domain=gplates.org >>>> >>>> The latter being potentially the fastest way to do this for a larger number of features. >>>> >>>> HTH, >>>> Christian >>>> >>>> >>>>> On 16 Dec 2018, at 15:41, Mark Brandon wrote: >>>>> >>>>> I am trying to import a list of seed points for the flow line calculation. I have successfully used of opening a gmt file (lon\tlat\r format, line by line) and that shows up in the list of loaded feature collections. (One can also paste the gmt file into the application with the same result.) But it is not clear to me how to convert this feature into a collection of seed points for the flow line calculation. >>>>> Best, >>>>> Mark >>>>> >>>>> _______________________________________________ >>>>> GPlates-discuss mailing list >>>>> GPlates-discuss at mailman.sydney.edu.au >>>>> https://mailman.sydney.edu.au/mailman/listinfo/gplates-discuss >>>>> >>>> >>>> _______________________________________________ >>>> GPlates-discuss mailing list >>>> GPlates-discuss at mailman.sydney.edu.au >>>> https://mailman.sydney.edu.au/mailman/listinfo/gplates-discuss >>> >>> _______________________________________________ >>> GPlates-discuss mailing list >>> GPlates-discuss at mailman.sydney.edu.au >>> https://mailman.sydney.edu.au/mailman/listinfo/gplates-discuss >>> >> >> _______________________________________________ >> GPlates-discuss mailing list >> GPlates-discuss at mailman.sydney.edu.au >> https://mailman.sydney.edu.au/mailman/listinfo/gplates-discuss > > _______________________________________________ > GPlates-discuss mailing list > GPlates-discuss at mailman.sydney.edu.au > https://mailman.sydney.edu.au/mailman/listinfo/gplates-discuss > -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 901 bytes Desc: Message signed with OpenPGP URL: From mark.brandon at yale.edu Mon Dec 17 09:19:42 2018 From: mark.brandon at yale.edu (Mark Brandon) Date: Sun, 16 Dec 2018 17:19:42 -0500 Subject: [GPlates-discuss] importing seed points In-Reply-To: References: <94972678-32A3-4E89-9362-A1FFA499E45F@yale.edu> <0E0AD30D-AB36-40DE-ABF4-B503A906C56B@paleoearthlabs.org> <6EBA7C8F-D4D8-4DF6-A1BF-AE5A0ADD9340@yale.edu> Message-ID: <5888B519-2350-49A5-9CE7-3E224692DD55@yale.edu> Christian, A major problem with listserver archives is that there is typically no way to search the archive. This is problem for both the gplates archives and the CIG archives. I guess we can hope that google does some indexing of those files, but I rarely see anything from these archives during my google searchers. Just a comment from the peanut gallery.... Best, Mark > On Dec 16, 2018, at 5:07 PM, Christian Heine wrote: > > Hi Mark, > > >> On 16 Dec 2018, at 21:45, Mark Brandon wrote: >> >> Christian, >> It might be worthwhile broadcasting the benefits of the "Copy to Dig" option. It is an awesome feature. > > As the mailing list archives are public it is now ;-) > >> There may be some documentation somewhere, but I have not found it yet. > > You're probably right - I don't think that this workflow is explicitly documented. > > @John/Michael - Maybe time for a GPlates Wiki for such things? > > Cheers, > Christian > > > >>> On Dec 16, 2018, at 3:41 PM, Christian Heine wrote: >>> >>> Hi Mark, >>> >>>> On 16 Dec 2018, at 20:35, Mark Brandon wrote: >>> >>> [...] >>> >>>> At that point, the "imported" geometry can be modified using the various digitize tools. To complete the important, select the New Multipoint Digitize Tool, and then select Create Feature below the New Geometry window on the right. You can select an appropriate feature option at that point. My my task, I select the Flow line option and continue from there... >>> >>> Yes that of course also works. I was under the impression that you wanted to create flowlines from new features. >>> >>> Make sure to save your flowlines as *.gpml files so that the flowline properties don't get lost. >>> >>> Cheers, >>> Christian >>> >>> >>> >>> >>> >>> >>>>> On Dec 16, 2018, at 2:00 PM, Christian Heine wrote: >>>>> >>>>> Hi Mark, >>>>> >>>>> Flowlines/seed points are a special kind of a beast - AFAIK you cannot save them in an OGR-type format (SHP, GMT etc) as come with a few special properties which are only available in GMPl (GPlates Markup Language). This is mainly because of the attached time sequence (gpml:times property) is a nested property which is not a trivial feat in the standard GIS format. >>>>> >>>>> Unless I am not mistaken, you'd have the following options : >>>>> >>>>> 1) Change the points individually in GPlates - that might be the best way if you have not too many points: Change the initial feature type mapping by selecting the point(s) in question, then ctrl+e to edit, change "feature type" (first line in the window that pops up) to "Flowline" and add a new property (click on 'add property' select gpml:times and adjust as needed) >>>>> >>>>> 2) Programmatically/manually wrap your point data in the correct GPML syntax for a flowline seed points using a text editor/script. A simple example with one point is attached. It is relatively straightforward but make sure to not break the XML. >>>>> >>>>> 3) A pyGPlates route would be to simply feed your point geometries to construct a flowline feature: https://protect-au.mimecast.com/s/iMfDCvl0PoClmVmQCQh-2H?domain=gplates.org >>>>> >>>>> The latter being potentially the fastest way to do this for a larger number of features. >>>>> >>>>> HTH, >>>>> Christian >>>>> >>>>> >>>>>> On 16 Dec 2018, at 15:41, Mark Brandon wrote: >>>>>> >>>>>> I am trying to import a list of seed points for the flow line calculation. I have successfully used of opening a gmt file (lon\tlat\r format, line by line) and that shows up in the list of loaded feature collections. (One can also paste the gmt file into the application with the same result.) But it is not clear to me how to convert this feature into a collection of seed points for the flow line calculation. >>>>>> Best, >>>>>> Mark >>>>>> >>>>>> _______________________________________________ >>>>>> GPlates-discuss mailing list >>>>>> GPlates-discuss at mailman.sydney.edu.au >>>>>> https://mailman.sydney.edu.au/mailman/listinfo/gplates-discuss >>>>>> >>>>> >>>>> _______________________________________________ >>>>> GPlates-discuss mailing list >>>>> GPlates-discuss at mailman.sydney.edu.au >>>>> https://mailman.sydney.edu.au/mailman/listinfo/gplates-discuss >>>> >>>> _______________________________________________ >>>> GPlates-discuss mailing list >>>> GPlates-discuss at mailman.sydney.edu.au >>>> https://mailman.sydney.edu.au/mailman/listinfo/gplates-discuss >>>> >>> >>> _______________________________________________ >>> GPlates-discuss mailing list >>> GPlates-discuss at mailman.sydney.edu.au >>> https://mailman.sydney.edu.au/mailman/listinfo/gplates-discuss >> >> _______________________________________________ >> GPlates-discuss mailing list >> GPlates-discuss at mailman.sydney.edu.au >> https://mailman.sydney.edu.au/mailman/listinfo/gplates-discuss >> > > _______________________________________________ > GPlates-discuss mailing list > GPlates-discuss at mailman.sydney.edu.au > https://mailman.sydney.edu.au/mailman/listinfo/gplates-discuss From mark.brandon at yale.edu Mon Dec 17 11:43:39 2018 From: mark.brandon at yale.edu (Mark Brandon) Date: Sun, 16 Dec 2018 19:43:39 -0500 Subject: [GPlates-discuss] Flow lines and ridge jumps In-Reply-To: References: <94972678-32A3-4E89-9362-A1FFA499E45F@yale.edu> <0E0AD30D-AB36-40DE-ABF4-B503A906C56B@paleoearthlabs.org> <6EBA7C8F-D4D8-4DF6-A1BF-AE5A0ADD9340@yale.edu> Message-ID: <137931BB-C524-4016-BCB5-F0716BBF79DE@yale.edu> I have been trying out GPlates' flow-line calculation to represent the evolution of the Juan de Fuca spreading center and adjacent plates over the last 40 Ma. As you might know, the JdF spreading center has had some ridge-jump events, one at 20 Ma and another at 5 Ma. My issue here concerns how to represent a change in the spreading center with respect to the flow-line calculation. I document this situation here in two ways, as shown in the two attached movies. The data sources for the reconstructions are: Mueller et al 2016 AREPS Isochrons (Reconstructed Geometries), Matthews et al 2016 GPC, Mesozoic-Cenozoic Plate Topologies (Reconstructed Geometries). The reference frame for the reconstructions is North America fixed, and the time interval is from 40 Ma to present. Note that the Yale email server strips out movie attachments, so the attachments here have extensions of .4pm to avoid this problem. Save the files and then convert the extensions to .mp4, and all will be good. The two reconstructions are: 1) Movie: "flowlines Pacific-Vancouver 40-0 Ma" The 40.1 Ma anomaly on the Pacific plate is set as the left-side endpoint for all flow lines, with the Vancouver plate on the "right side". 2) Movie: "flowlines Pacific-JdF 40-0 Ma.mp4" The modern Pacific/Juan de Fuca boundary is set as a "spreading center", with the flow lines calculated symmetric relative to that reference. (As an aside, I don't know why the flow-line calculation does not work in this case for the time interval between 40 and 29 Ma.) The first reconstruction provides a clear correspondence between the seed points and the coeval spreading center during the early part of the reconstruction. This relationship breaks down after the ridge jumps at 20 and 5 Ma. The second reconstruction shows a poor correspondence between seed point and the coeval spreading center during the early part of the reconstruction. That situation switches to a good correspondence during the later part of the reconstruction. For course, this is all expected given that the seed points for the first case are based on the initial configuration of the spreading center, and the second case, on the final configuration of the spreading center. The first case does a good job representing the motion of the bounding 40.1 Ma isochrons move away from the spreading center. The second case does a good job representing the age distribution near the final spreading center. Both calculations seem to give the same estimate of the displacement field relative to the coeval plate boundary (aka active spreading center). This last point is important, but difficult to precisely verify from these examples. >> It would be useful to hear from the GPlates programmers about this last statement. My objective is not the displacement field, but rather the plate age around the spreading center. My thought at this point is that the plate age might be represented by the minimum of the two age fields. In other words, a ridge jump operates to introducing younger lithosphere in the area around the new ridge. That said, I think there may be some ridge-jump situations that can defeat this simple view. I am hoping to get feedback from others, especially those who have already thought through this situation... Best, Mark -------------- next part -------------- A non-text attachment was scrubbed... Name: flowlines Pacific-Vancouver 40-0 Ma.4pm Type: application/octet-stream Size: 1812976 bytes Desc: not available URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: flowlines Pacific-JdF 40-0 Ma.4pm Type: application/octet-stream Size: 849392 bytes Desc: not available URL: -------------- next part -------------- From simon.williams at sydney.edu.au Mon Dec 17 15:38:44 2018 From: simon.williams at sydney.edu.au (Simon Williams) Date: Mon, 17 Dec 2018 04:38:44 +0000 Subject: [GPlates-discuss] Reconstruct rasters with pyGPlates In-Reply-To: References: Message-ID: Hi Ben, pygplates does not currently have an official raster capability that matches the same capability in GPlates, in the sense that you cannot simply specify a GPlates-readable raster file, load it in to a feature collection, do stuff with it with the same speed as GPlates using the GPU. Also, for the purposes of this reply I?ll assume that when you say ?deformed?, you mean reconstructed based on rigid plate motions rather than a reconstruction model with actual ?deforming? regions. If you do mean the latter, then can stop reading now?.. Instead, there does exist some experimental code built on top of pygplates to make raster reconstruction more efficient than it would be by simply treating each grid node as a point (or multipoint). [ One of the main issues for this kind of calculation is that the step where each grid node is assigned a plateid would be much slower in python compared to how it is done within GPlates. The atom_utils repository contains some functions that John wrote to speed up this process using spatial trees, which typically makes a big difference. ] John may have a better (more well documented) example, the best one I can think of can be found here: https://protect-au.mimecast.com/s/1CRcCgZowLHBMZrAiNAYi5?domain=github.com See specifically the function ?reconstruct_raster? An example usage would be: Raster = GplatesRaster(filename) (reconstructed_point_lons, reconstructed_point_lats, reconstructed_zvalues) = reconstruct_raster(raster, static_polygons, rotation_model, from_time, to_time, grid_sampling=2.0) plt.scatter(reconstructed_point_lons,unreconstructed_point_lats, c=reconstructed_zvalues) Where static_polygons is a list of polygon features required for the plateid assignments, rotation_model is an associated set of rotations to make these polygons move, from_time would be zero for a raster in present-day coordinates and to_time would be the desired reconstruction time. Note that: - This code is not exactly working on 2D numpy arrays, rather a feature of the (even more experimental) GPlates raster class, which is assumed to be coming from a netcdf file, see here https://protect-au.mimecast.com/s/JgGPCjZrzqHOWQ2nCRrM7t?domain=github.com. The class contains arrays of the lats and longs of the grid nodes as well as an array of the z values. You could modify the first few lines of the reconstruct_raster function to avoid using this class. - The code returns arrays of reconstructed longs and lats together with z values, but not on a regular lat-long grid - you?d need to to resample as an extra step. - if you try to use this code and hit unfound dependency problems then feel free to let me know. Cheers, Simon On 16 Dec 2018, at 11:22 am, Ben Mather > wrote: Hi team! I was wondering if it is possible to reconstruct raster images back in time like it is in regular GPlates? It would be very useful to, say, have a 2D numpy array that could be deformed with respect to a rotation model. Cheers, Ben Dr. Ben Mather | Computational Geophysicist Room 418, Madsen Building F09 School of Geoscience, Faculty of Science The University of Sydney, NSW 2006 m +61 422 470 117 w benmather.info t twitter.com/BenRMather _______________________________________________ GPlates-discuss mailing list GPlates-discuss at mailman.sydney.edu.au https://mailman.sydney.edu.au/mailman/listinfo/gplates-discuss -------------- next part -------------- An HTML attachment was scrubbed... URL: From Nicky.Wright at anu.edu.au Tue Dec 18 12:13:34 2018 From: Nicky.Wright at anu.edu.au (Nicky Wright) Date: Tue, 18 Dec 2018 01:13:34 +0000 Subject: [GPlates-discuss] Flow lines and ridge jumps In-Reply-To: <137931BB-C524-4016-BCB5-F0716BBF79DE@yale.edu> References: <94972678-32A3-4E89-9362-A1FFA499E45F@yale.edu> <0E0AD30D-AB36-40DE-ABF4-B503A906C56B@paleoearthlabs.org> <6EBA7C8F-D4D8-4DF6-A1BF-AE5A0ADD9340@yale.edu> <137931BB-C524-4016-BCB5-F0716BBF79DE@yale.edu> Message-ID: Hi Mark, At what time are you looking for plate age around the spreading centre? I will admit I haven?t thought about this at all lately. As to why the flowline calculation doesn?t work between 40-29 Ma for your second case (Pacific-JdF): The JdF rotations (plate 910 in the rotation file) are relative to the Pacific plate (plate 901), and have no relative motion with the Pacific plate before 28.3 Ma. To get it to work for the entire time period, you can: 1. Create the flowlines for your second case (present-day JdF ridge) using plate 903 (Vancouver) instead - the flowlines will work for the entire time period and will actually use the 910-901 rotations (JdF-PAC) between 0 and 28.3 Ma (this is the easiest option) 2. If you?re comfortable editing the rotation file itself and you?d rather stick to plate 910 for your present-day geometry (I know the colour difference in the flowline points might help a little here), you can open the rotation file in a text editor and replace the rotations for 910 with? (I?ve copied from the existing JdF 28.3 Ma rotation from Matthews et al 2016 here): 910 28.3 81.35 -117.91 -30.67 901 !JFC-PAC @REF Wright_++_2016 @DOI"10.1016/j.earscirev.2015.11.015" @CHRONID"c10n1ny" 910 28.3 0.0 0.0 0.0 903 ! JFC-VAN 910 250.0 0.0 0.0 0.0 903 ! JFC-VAN Cheers, Nicky From: GPlates-discuss on behalf of Mark Brandon Reply-To: GPlates general discussion mailing list Date: Monday, 17 December 2018 at 11:44 am To: GPlates general discussion mailing list Subject: [GPlates-discuss] Flow lines and ridge jumps I have been trying out GPlates' flow-line calculation to represent the evolution of the Juan de Fuca spreading center and adjacent plates over the last 40 Ma. As you might know, the JdF spreading center has had some ridge-jump events, one at 20 Ma and another at 5 Ma. My issue here concerns how to represent a change in the spreading center with respect to the flow-line calculation. I document this situation here in two ways, as shown in the two attached movies. The data sources for the reconstructions are: Mueller et al 2016 AREPS Isochrons (Reconstructed Geometries), Matthews et al 2016 GPC, Mesozoic-Cenozoic Plate Topologies (Reconstructed Geometries). The reference frame for the reconstructions is North America fixed, and the time interval is from 40 Ma to present. Note that the Yale email server strips out movie attachments, so the attachments here have extensions of .4pm to avoid this problem. Save the files and then convert the extensions to .mp4, and all will be good. The two reconstructions are: 1) Movie: "flowlines Pacific-Vancouver 40-0 Ma" The 40.1 Ma anomaly on the Pacific plate is set as the left-side endpoint for all flow lines, with the Vancouver plate on the "right side". 2) Movie: "flowlines Pacific-JdF 40-0 Ma.mp4" The modern Pacific/Juan de Fuca boundary is set as a "spreading center", with the flow lines calculated symmetric relative to that reference. (As an aside, I don't know why the flow-line calculation does not work in this case for the time interval between 40 and 29 Ma.) The first reconstruction provides a clear correspondence between the seed points and the coeval spreading center during the early part of the reconstruction. This relationship breaks down after the ridge jumps at 20 and 5 Ma. The second reconstruction shows a poor correspondence between seed point and the coeval spreading center during the early part of the reconstruction. That situation switches to a good correspondence during the later part of the reconstruction. For course, this is all expected given that the seed points for the first case are based on the initial configuration of the spreading center, and the second case, on the final configuration of the spreading center. The first case does a good job representing the motion of the bounding 40.1 Ma isochrons move away from the spreading center. The second case does a good job representing the age distribution near the final spreading center. Both calculations seem to give the same estimate of the displacement field relative to the coeval plate boundary (aka active spreading center). This last point is important, but difficult to precisely verify from these examples. >> It would be useful to hear from the GPlates programmers about this last statement. My objective is not the displacement field, but rather the plate age around the spreading center. My thought at this point is that the plate age might be represented by the minimum of the two age fields. In other words, a ridge jump operates to introducing younger lithosphere in the area around the new ridge. That said, I think there may be some ridge-jump situations that can defeat this simple view. I am hoping to get feedback from others, especially those who have already thought through this situation... Best, Mark _______________________________________________ GPlates-discuss mailing list GPlates-discuss at mailman.sydney.edu.au https://mailman.sydney.edu.au/mailman/listinfo/gplates-discuss -------------- next part -------------- An HTML attachment was scrubbed... URL: From mark.brandon at yale.edu Wed Dec 19 00:30:11 2018 From: mark.brandon at yale.edu (Mark Brandon) Date: Tue, 18 Dec 2018 08:30:11 -0500 Subject: [GPlates-discuss] Flow lines and ridge jumps In-Reply-To: References: <94972678-32A3-4E89-9362-A1FFA499E45F@yale.edu> <0E0AD30D-AB36-40DE-ABF4-B503A906C56B@paleoearthlabs.org> <6EBA7C8F-D4D8-4DF6-A1BF-AE5A0ADD9340@yale.edu> <137931BB-C524-4016-BCB5-F0716BBF79DE@yale.edu> Message-ID: <1F6287FA-899D-4FE8-AF87-14E138309E6F@yale.edu> Nicky Thanks a bunch.... Your comments are very helpful. In addition, I realized this morning that I probably need to calculate flow points as a function of the intervals between ridge jumps. I should be able to proceed okay now. Thanks again!! Best, Mark > On Dec 17, 2018, at 8:13 PM, Nicky Wright wrote: > > Hi Mark, > > At what time are you looking for plate age around the spreading centre? I will admit I haven?t thought about this at all lately. > > As to why the flowline calculation doesn?t work between 40-29 Ma for your second case (Pacific-JdF): > The JdF rotations (plate 910 in the rotation file) are relative to the Pacific plate (plate 901), and have no relative motion with the Pacific plate before 28.3 Ma. > > To get it to work for the entire time period, you can: > ? Create the flowlines for your second case (present-day JdF ridge) using plate 903 (Vancouver) instead - the flowlines will work for the entire time period and will actually use the 910-901 rotations (JdF-PAC) between 0 and 28.3 Ma (this is the easiest option) > ? If you?re comfortable editing the rotation file itself and you?d rather stick to plate 910 for your present-day geometry (I know the colour difference in the flowline points might help a little here), you can open the rotation file in a text editor and replace the rotations for 910 with? (I?ve copied from the existing JdF 28.3 Ma rotation from Matthews et al 2016 here): > 910 28.3 81.35 -117.91 -30.67 901 !JFC-PAC @REF Wright_++_2016 @DOI"10.1016/j.earscirev.2015.11.015" @CHRONID"c10n1ny" > 910 28.3 0.0 0.0 0.0 903 ! JFC-VAN > 910 250.0 0.0 0.0 0.0 903 ! JFC-VAN > > Cheers, > Nicky > > > From: GPlates-discuss on behalf of Mark Brandon > Reply-To: GPlates general discussion mailing list > Date: Monday, 17 December 2018 at 11:44 am > To: GPlates general discussion mailing list > Subject: [GPlates-discuss] Flow lines and ridge jumps > > > I have been trying out GPlates' flow-line calculation to represent the evolution of the Juan de Fuca spreading center and adjacent plates over the last 40 Ma. As you might know, the JdF spreading center has had some ridge-jump events, one at 20 Ma and another at 5 Ma. My issue here concerns how to represent a change in the spreading center with respect to the flow-line calculation. > > I document this situation here in two ways, as shown in the two attached movies. The data sources for the reconstructions are: Mueller et al 2016 AREPS Isochrons (Reconstructed Geometries), Matthews et al 2016 GPC, Mesozoic-Cenozoic Plate Topologies (Reconstructed Geometries). The reference frame for the reconstructions is North America fixed, and the time interval is from 40 Ma to present. > > Note that the Yale email server strips out movie attachments, so the attachments here have extensions of .4pm to avoid this problem. Save the files and then convert the extensions to .mp4, and all will be good. > > The two reconstructions are: > > 1) Movie: "flowlines Pacific-Vancouver 40-0 Ma" > The 40.1 Ma anomaly on the Pacific plate is set as the left-side endpoint for all flow lines, with the Vancouver plate on the "right side". > > 2) Movie: "flowlines Pacific-JdF 40-0 Ma.mp4" > The modern Pacific/Juan de Fuca boundary is set as a "spreading center", with the flow lines calculated symmetric relative to that reference. (As an aside, I don't know why the flow-line calculation does not work in this case for the time interval between 40 and 29 Ma.) > > The first reconstruction provides a clear correspondence between the seed points and the coeval spreading center during the early part of the reconstruction. This relationship breaks down after the ridge jumps at 20 and 5 Ma. > > The second reconstruction shows a poor correspondence between seed point and the coeval spreading center during the early part of the reconstruction. That situation switches to a good correspondence during the later part of the reconstruction. > > For course, this is all expected given that the seed points for the first case are based on the initial configuration of the spreading center, and the second case, on the final configuration of the spreading center. > > The first case does a good job representing the motion of the bounding 40.1 Ma isochrons move away from the spreading center. The second case does a good job representing the age distribution near the final spreading center. Both calculations seem to give the same estimate of the displacement field relative to the coeval plate boundary (aka active spreading center). This last point is important, but difficult to precisely verify from these examples. > > >> It would be useful to hear from the GPlates programmers about this last statement. > > My objective is not the displacement field, but rather the plate age around the spreading center. My thought at this point is that the plate age might be represented by the minimum of the two age fields. In other words, a ridge jump operates to introducing younger lithosphere in the area around the new ridge. That said, I think there may be some ridge-jump situations that can defeat this simple view. > > I am hoping to get feedback from others, especially those who have already thought through this situation... > > Best, > Mark > > > > > _______________________________________________ > GPlates-discuss mailing list > GPlates-discuss at mailman.sydney.edu.au > https://mailman.sydney.edu.au/mailman/listinfo/gplates-discuss > _______________________________________________ > GPlates-discuss mailing list > GPlates-discuss at mailman.sydney.edu.au > https://mailman.sydney.edu.au/mailman/listinfo/gplates-discuss From mark.brandon at yale.edu Fri Dec 21 09:50:18 2018 From: mark.brandon at yale.edu (Mark Brandon) Date: Thu, 20 Dec 2018 17:50:18 -0500 Subject: [GPlates-discuss] Flow lines and ridge jumps In-Reply-To: References: <94972678-32A3-4E89-9362-A1FFA499E45F@yale.edu> <0E0AD30D-AB36-40DE-ABF4-B503A906C56B@paleoearthlabs.org> <6EBA7C8F-D4D8-4DF6-A1BF-AE5A0ADD9340@yale.edu> <137931BB-C524-4016-BCB5-F0716BBF79DE@yale.edu> Message-ID: <671CF1A8-B412-4DA7-8849-B8E890C0A570@yale.edu> Nicky and others, Given this discussion about flow lines, it may be useful to ask how one might construct "synthetic isochrons" in GPlates. The review paper linked below has a discussion about this idea. https://protect-au.mimecast.com/s/AMWFC91ZkQtjNYV0UoJMX7?domain=cambridge.org The objective is nearly identical to producing an grid for plate age. To ask more directly: Is there a simple way to create synthetic isochrons in GPlates? Best, Mark > On Dec 17, 2018, at 8:13 PM, Nicky Wright wrote: > > Hi Mark, > > At what time are you looking for plate age around the spreading centre? I will admit I haven?t thought about this at all lately. > > As to why the flowline calculation doesn?t work between 40-29 Ma for your second case (Pacific-JdF): > The JdF rotations (plate 910 in the rotation file) are relative to the Pacific plate (plate 901), and have no relative motion with the Pacific plate before 28.3 Ma. > > To get it to work for the entire time period, you can: > ? Create the flowlines for your second case (present-day JdF ridge) using plate 903 (Vancouver) instead - the flowlines will work for the entire time period and will actually use the 910-901 rotations (JdF-PAC) between 0 and 28.3 Ma (this is the easiest option) > ? If you?re comfortable editing the rotation file itself and you?d rather stick to plate 910 for your present-day geometry (I know the colour difference in the flowline points might help a little here), you can open the rotation file in a text editor and replace the rotations for 910 with? (I?ve copied from the existing JdF 28.3 Ma rotation from Matthews et al 2016 here): > 910 28.3 81.35 -117.91 -30.67 901 !JFC-PAC @REF Wright_++_2016 @DOI"10.1016/j.earscirev.2015.11.015" @CHRONID"c10n1ny" > 910 28.3 0.0 0.0 0.0 903 ! JFC-VAN > 910 250.0 0.0 0.0 0.0 903 ! JFC-VAN > > Cheers, > Nicky > > > From: GPlates-discuss on behalf of Mark Brandon > Reply-To: GPlates general discussion mailing list > Date: Monday, 17 December 2018 at 11:44 am > To: GPlates general discussion mailing list > Subject: [GPlates-discuss] Flow lines and ridge jumps > > > I have been trying out GPlates' flow-line calculation to represent the evolution of the Juan de Fuca spreading center and adjacent plates over the last 40 Ma. As you might know, the JdF spreading center has had some ridge-jump events, one at 20 Ma and another at 5 Ma. My issue here concerns how to represent a change in the spreading center with respect to the flow-line calculation. > > I document this situation here in two ways, as shown in the two attached movies. The data sources for the reconstructions are: Mueller et al 2016 AREPS Isochrons (Reconstructed Geometries), Matthews et al 2016 GPC, Mesozoic-Cenozoic Plate Topologies (Reconstructed Geometries). The reference frame for the reconstructions is North America fixed, and the time interval is from 40 Ma to present. > > Note that the Yale email server strips out movie attachments, so the attachments here have extensions of .4pm to avoid this problem. Save the files and then convert the extensions to .mp4, and all will be good. > > The two reconstructions are: > > 1) Movie: "flowlines Pacific-Vancouver 40-0 Ma" > The 40.1 Ma anomaly on the Pacific plate is set as the left-side endpoint for all flow lines, with the Vancouver plate on the "right side". > > 2) Movie: "flowlines Pacific-JdF 40-0 Ma.mp4" > The modern Pacific/Juan de Fuca boundary is set as a "spreading center", with the flow lines calculated symmetric relative to that reference. (As an aside, I don't know why the flow-line calculation does not work in this case for the time interval between 40 and 29 Ma.) > > The first reconstruction provides a clear correspondence between the seed points and the coeval spreading center during the early part of the reconstruction. This relationship breaks down after the ridge jumps at 20 and 5 Ma. > > The second reconstruction shows a poor correspondence between seed point and the coeval spreading center during the early part of the reconstruction. That situation switches to a good correspondence during the later part of the reconstruction. > > For course, this is all expected given that the seed points for the first case are based on the initial configuration of the spreading center, and the second case, on the final configuration of the spreading center. > > The first case does a good job representing the motion of the bounding 40.1 Ma isochrons move away from the spreading center. The second case does a good job representing the age distribution near the final spreading center. Both calculations seem to give the same estimate of the displacement field relative to the coeval plate boundary (aka active spreading center). This last point is important, but difficult to precisely verify from these examples. > > >> It would be useful to hear from the GPlates programmers about this last statement. > > My objective is not the displacement field, but rather the plate age around the spreading center. My thought at this point is that the plate age might be represented by the minimum of the two age fields. In other words, a ridge jump operates to introducing younger lithosphere in the area around the new ridge. That said, I think there may be some ridge-jump situations that can defeat this simple view. > > I am hoping to get feedback from others, especially those who have already thought through this situation... > > Best, > Mark > > > > > _______________________________________________ > GPlates-discuss mailing list > GPlates-discuss at mailman.sydney.edu.au > https://mailman.sydney.edu.au/mailman/listinfo/gplates-discuss > _______________________________________________ > GPlates-discuss mailing list > GPlates-discuss at mailman.sydney.edu.au > https://mailman.sydney.edu.au/mailman/listinfo/gplates-discuss From buddavis at utexas.edu Fri Dec 21 11:58:27 2018 From: buddavis at utexas.edu (Bud Davis) Date: Thu, 20 Dec 2018 19:58:27 -0500 Subject: [GPlates-discuss] Flow lines and ridge jumps In-Reply-To: <671CF1A8-B412-4DA7-8849-B8E890C0A570@yale.edu> References: <94972678-32A3-4E89-9362-A1FFA499E45F@yale.edu> <0E0AD30D-AB36-40DE-ABF4-B503A906C56B@paleoearthlabs.org> <6EBA7C8F-D4D8-4DF6-A1BF-AE5A0ADD9340@yale.edu> <137931BB-C524-4016-BCB5-F0716BBF79DE@yale.edu> <671CF1A8-B412-4DA7-8849-B8E890C0A570@yale.edu> Message-ID: The very simplest way I?ve done it is to just export a series of ridge shapefiles at each time step your interested in. Set the relative plate to the plate on one side of the ridge, and do the export of the ridge shapefile. Then set to the relative plate on the other side of the ridge. You can easily grid these ridges by assigning them an age and clipping them to the plate you?re interested in in a GIS program. Cheers, Bud Davis On Thu, Dec 20, 2018 at 5:50 PM Mark Brandon wrote: > Nicky and others, > Given this discussion about flow lines, it may be useful to ask how one > might construct "synthetic isochrons" in GPlates. > The review paper linked below has a discussion about this idea. > > > https://protect-au.mimecast.com/s/2YFEC1WZXriXB1EXhL8Wfy?domain=cambridge.org > > The objective is nearly identical to producing an grid for plate age. To > ask more directly: Is there a simple way to create synthetic isochrons in > GPlates? > Best, > Mark > > > On Dec 17, 2018, at 8:13 PM, Nicky Wright > wrote: > > > > Hi Mark, > > > > At what time are you looking for plate age around the spreading centre? > I will admit I haven?t thought about this at all lately. > > > > As to why the flowline calculation doesn?t work between 40-29 Ma for > your second case (Pacific-JdF): > > The JdF rotations (plate 910 in the rotation file) are relative to the > Pacific plate (plate 901), and have no relative motion with the Pacific > plate before 28.3 Ma. > > > > To get it to work for the entire time period, you can: > > ? Create the flowlines for your second case (present-day JdF > ridge) using plate 903 (Vancouver) instead - the flowlines will work for > the entire time period and will actually use the 910-901 rotations > (JdF-PAC) between 0 and 28.3 Ma (this is the easiest option) > > ? If you?re comfortable editing the rotation file itself and you?d > rather stick to plate 910 for your present-day geometry (I know the colour > difference in the flowline points might help a little here), you can open > the rotation file in a text editor and replace the rotations for 910 with? > (I?ve copied from the existing JdF 28.3 Ma rotation from Matthews et al > 2016 here): > > 910 28.3 81.35 -117.91 -30.67 901 !JFC-PAC @REF Wright_++_2016 > @DOI"10.1016/j.earscirev.2015.11.015" @CHRONID"c10n1ny" > > 910 28.3 0.0 0.0 0.0 903 ! JFC-VAN > > 910 250.0 0.0 0.0 0.0 903 ! JFC-VAN > > > > Cheers, > > Nicky > > > > > > From: GPlates-discuss > on behalf of Mark Brandon > > Reply-To: GPlates general discussion mailing list < > gplates-discuss at mailman.sydney.edu.au> > > Date: Monday, 17 December 2018 at 11:44 am > > To: GPlates general discussion mailing list < > gplates-discuss at mailman.sydney.edu.au> > > Subject: [GPlates-discuss] Flow lines and ridge jumps > > > > > > I have been trying out GPlates' flow-line calculation to represent the > evolution of the Juan de Fuca spreading center and adjacent plates over the > last 40 Ma. As you might know, the JdF spreading center has had some > ridge-jump events, one at 20 Ma and another at 5 Ma. My issue here concerns > how to represent a change in the spreading center with respect to the > flow-line calculation. > > > > I document this situation here in two ways, as shown in the two attached > movies. The data sources for the reconstructions are: Mueller et al 2016 > AREPS Isochrons (Reconstructed Geometries), Matthews et al 2016 GPC, > Mesozoic-Cenozoic Plate Topologies (Reconstructed Geometries). The > reference frame for the reconstructions is North America fixed, and the > time interval is from 40 Ma to present. > > > > Note that the Yale email server strips out movie attachments, so the > attachments here have extensions of .4pm to avoid this problem. Save the > files and then convert the extensions to .mp4, and all will be good. > > > > The two reconstructions are: > > > > 1) Movie: "flowlines Pacific-Vancouver 40-0 Ma" > > The 40.1 Ma anomaly on the Pacific plate is set as the left-side > endpoint for all flow lines, with the Vancouver plate on the "right side". > > > > 2) Movie: "flowlines Pacific-JdF 40-0 Ma.mp4" > > The modern Pacific/Juan de Fuca boundary is set as a "spreading center", > with the flow lines calculated symmetric relative to that reference. (As an > aside, I don't know why the flow-line calculation does not work in this > case for the time interval between 40 and 29 Ma.) > > > > The first reconstruction provides a clear correspondence between the > seed points and the coeval spreading center during the early part of the > reconstruction. This relationship breaks down after the ridge jumps at 20 > and 5 Ma. > > > > The second reconstruction shows a poor correspondence between seed point > and the coeval spreading center during the early part of the > reconstruction. That situation switches to a good correspondence during the > later part of the reconstruction. > > > > For course, this is all expected given that the seed points for the > first case are based on the initial configuration of the spreading center, > and the second case, on the final configuration of the spreading center. > > > > The first case does a good job representing the motion of the bounding > 40.1 Ma isochrons move away from the spreading center. The second case does > a good job representing the age distribution near the final spreading > center. Both calculations seem to give the same estimate of the > displacement field relative to the coeval plate boundary (aka active > spreading center). This last point is important, but difficult to precisely > verify from these examples. > > > > >> It would be useful to hear from the GPlates programmers about this > last statement. > > > > My objective is not the displacement field, but rather the plate age > around the spreading center. My thought at this point is that the plate age > might be represented by the minimum of the two age fields. In other words, > a ridge jump operates to introducing younger lithosphere in the area around > the new ridge. That said, I think there may be some ridge-jump situations > that can defeat this simple view. > > > > I am hoping to get feedback from others, especially those who have > already thought through this situation... > > > > Best, > > Mark > > > > > > > > > > _______________________________________________ > > GPlates-discuss mailing list > > GPlates-discuss at mailman.sydney.edu.au > > https://mailman.sydney.edu.au/mailman/listinfo/gplates-discuss > > _______________________________________________ > > GPlates-discuss mailing list > > GPlates-discuss at mailman.sydney.edu.au > > https://mailman.sydney.edu.au/mailman/listinfo/gplates-discuss > > _______________________________________________ > GPlates-discuss mailing list > GPlates-discuss at mailman.sydney.edu.au > https://mailman.sydney.edu.au/mailman/listinfo/gplates-discuss > > -- Joshua "Bud" Davis Graduate Research Assistant University of Texas-Austin Institute for Geophysics buddavis at utexas.edu 904-556-4401 -------------- next part -------------- An HTML attachment was scrubbed... URL: From simon.williams at sydney.edu.au Fri Dec 21 12:43:16 2018 From: simon.williams at sydney.edu.au (Simon Williams) Date: Fri, 21 Dec 2018 01:43:16 +0000 Subject: [GPlates-discuss] Flow lines and ridge jumps In-Reply-To: References: <94972678-32A3-4E89-9362-A1FFA499E45F@yale.edu> <0E0AD30D-AB36-40DE-ABF4-B503A906C56B@paleoearthlabs.org> <6EBA7C8F-D4D8-4DF6-A1BF-AE5A0ADD9340@yale.edu> <137931BB-C524-4016-BCB5-F0716BBF79DE@yale.edu> <671CF1A8-B412-4DA7-8849-B8E890C0A570@yale.edu> Message-ID: Hi Mark, Another option is the following: Suppose you have a line geometry that represents a ridge at a certain moment in time, and you are viewing it in GPlates (with the reconstruction time set to the time you want to make two conjugate isochrons for) - select the feature - click on ?Copy Geometry to Digitize Tool? - click on ?Create Feature? - Make sure you select ?Isochron? as the feature type - Ensure the Plate ID and Conjugate Plate ID are set to the plateids for the two plates in question (I?m assuming you have this in a rotation file already), and set the appearance time to be the current reconstruction time - tick the box ?Create conjugate feature' Once the feature is created, you should get two lines. They will be exactly superimposed at the current reconstruction, but would move in opposite direction as you move towards present-day. This would need to be repeated for each time you want to make isochrons for. Cheers, Simon On 21 Dec 2018, at 11:58 am, Bud Davis > wrote: The very simplest way I?ve done it is to just export a series of ridge shapefiles at each time step your interested in. Set the relative plate to the plate on one side of the ridge, and do the export of the ridge shapefile. Then set to the relative plate on the other side of the ridge. You can easily grid these ridges by assigning them an age and clipping them to the plate you?re interested in in a GIS program. Cheers, Bud Davis On Thu, Dec 20, 2018 at 5:50 PM Mark Brandon > wrote: Nicky and others, Given this discussion about flow lines, it may be useful to ask how one might construct "synthetic isochrons" in GPlates. The review paper linked below has a discussion about this idea. https://protect-au.mimecast.com/s/U8I-Cp8AJQtZO0p7tPJ99L?domain=cambridge.org The objective is nearly identical to producing an grid for plate age. To ask more directly: Is there a simple way to create synthetic isochrons in GPlates? Best, Mark > On Dec 17, 2018, at 8:13 PM, Nicky Wright > wrote: > > Hi Mark, > > At what time are you looking for plate age around the spreading centre? I will admit I haven?t thought about this at all lately. > > As to why the flowline calculation doesn?t work between 40-29 Ma for your second case (Pacific-JdF): > The JdF rotations (plate 910 in the rotation file) are relative to the Pacific plate (plate 901), and have no relative motion with the Pacific plate before 28.3 Ma. > > To get it to work for the entire time period, you can: > ? Create the flowlines for your second case (present-day JdF ridge) using plate 903 (Vancouver) instead - the flowlines will work for the entire time period and will actually use the 910-901 rotations (JdF-PAC) between 0 and 28.3 Ma (this is the easiest option) > ? If you?re comfortable editing the rotation file itself and you?d rather stick to plate 910 for your present-day geometry (I know the colour difference in the flowline points might help a little here), you can open the rotation file in a text editor and replace the rotations for 910 with? (I?ve copied from the existing JdF 28.3 Ma rotation from Matthews et al 2016 here): > 910 28.3 81.35 -117.91 -30.67 901 !JFC-PAC @REF Wright_++_2016 @DOI"10.1016/j.earscirev.2015.11.015" @CHRONID"c10n1ny" > 910 28.3 0.0 0.0 0.0 903 ! JFC-VAN > 910 250.0 0.0 0.0 0.0 903 ! JFC-VAN > > Cheers, > Nicky > > > From: GPlates-discuss > on behalf of Mark Brandon > > Reply-To: GPlates general discussion mailing list > > Date: Monday, 17 December 2018 at 11:44 am > To: GPlates general discussion mailing list > > Subject: [GPlates-discuss] Flow lines and ridge jumps > > > I have been trying out GPlates' flow-line calculation to represent the evolution of the Juan de Fuca spreading center and adjacent plates over the last 40 Ma. As you might know, the JdF spreading center has had some ridge-jump events, one at 20 Ma and another at 5 Ma. My issue here concerns how to represent a change in the spreading center with respect to the flow-line calculation. > > I document this situation here in two ways, as shown in the two attached movies. The data sources for the reconstructions are: Mueller et al 2016 AREPS Isochrons (Reconstructed Geometries), Matthews et al 2016 GPC, Mesozoic-Cenozoic Plate Topologies (Reconstructed Geometries). The reference frame for the reconstructions is North America fixed, and the time interval is from 40 Ma to present. > > Note that the Yale email server strips out movie attachments, so the attachments here have extensions of .4pm to avoid this problem. Save the files and then convert the extensions to .mp4, and all will be good. > > The two reconstructions are: > > 1) Movie: "flowlines Pacific-Vancouver 40-0 Ma" > The 40.1 Ma anomaly on the Pacific plate is set as the left-side endpoint for all flow lines, with the Vancouver plate on the "right side". > > 2) Movie: "flowlines Pacific-JdF 40-0 Ma.mp4" > The modern Pacific/Juan de Fuca boundary is set as a "spreading center", with the flow lines calculated symmetric relative to that reference. (As an aside, I don't know why the flow-line calculation does not work in this case for the time interval between 40 and 29 Ma.) > > The first reconstruction provides a clear correspondence between the seed points and the coeval spreading center during the early part of the reconstruction. This relationship breaks down after the ridge jumps at 20 and 5 Ma. > > The second reconstruction shows a poor correspondence between seed point and the coeval spreading center during the early part of the reconstruction. That situation switches to a good correspondence during the later part of the reconstruction. > > For course, this is all expected given that the seed points for the first case are based on the initial configuration of the spreading center, and the second case, on the final configuration of the spreading center. > > The first case does a good job representing the motion of the bounding 40.1 Ma isochrons move away from the spreading center. The second case does a good job representing the age distribution near the final spreading center. Both calculations seem to give the same estimate of the displacement field relative to the coeval plate boundary (aka active spreading center). This last point is important, but difficult to precisely verify from these examples. > > >> It would be useful to hear from the GPlates programmers about this last statement. > > My objective is not the displacement field, but rather the plate age around the spreading center. My thought at this point is that the plate age might be represented by the minimum of the two age fields. In other words, a ridge jump operates to introducing younger lithosphere in the area around the new ridge. That said, I think there may be some ridge-jump situations that can defeat this simple view. > > I am hoping to get feedback from others, especially those who have already thought through this situation... > > Best, > Mark > > > > > _______________________________________________ > GPlates-discuss mailing list > GPlates-discuss at mailman.sydney.edu.au > https://mailman.sydney.edu.au/mailman/listinfo/gplates-discuss > _______________________________________________ > GPlates-discuss mailing list > GPlates-discuss at mailman.sydney.edu.au > https://mailman.sydney.edu.au/mailman/listinfo/gplates-discuss _______________________________________________ GPlates-discuss mailing list GPlates-discuss at mailman.sydney.edu.au https://mailman.sydney.edu.au/mailman/listinfo/gplates-discuss -- Joshua "Bud" Davis Graduate Research Assistant University of Texas-Austin Institute for Geophysics buddavis at utexas.edu 904-556-4401 _______________________________________________ GPlates-discuss mailing list GPlates-discuss at mailman.sydney.edu.au https://mailman.sydney.edu.au/mailman/listinfo/gplates-discuss -------------- next part -------------- An HTML attachment was scrubbed... URL: From mark.brandon at yale.edu Fri Dec 21 13:50:55 2018 From: mark.brandon at yale.edu (Mark Brandon) Date: Thu, 20 Dec 2018 21:50:55 -0500 Subject: [GPlates-discuss] Flow lines and ridge jumps In-Reply-To: References: <94972678-32A3-4E89-9362-A1FFA499E45F@yale.edu> <0E0AD30D-AB36-40DE-ABF4-B503A906C56B@paleoearthlabs.org> <6EBA7C8F-D4D8-4DF6-A1BF-AE5A0ADD9340@yale.edu> <137931BB-C524-4016-BCB5-F0716BBF79DE@yale.edu> <671CF1A8-B412-4DA7-8849-B8E890C0A570@yale.edu> Message-ID: <201223D8-7ADB-4FC1-A1CA-53081A683AEE@yale.edu> Simon and Bud, Thanks for your simple and clever solutions!! Best, Mark > On Dec 20, 2018, at 8:43 PM, Simon Williams wrote: > > Hi Mark, > > Another option is the following: > > Suppose you have a line geometry that represents a ridge at a certain moment in time, and you are viewing it in GPlates (with the reconstruction time set to the time you want to make two conjugate isochrons for) > > - select the feature > - click on ?Copy Geometry to Digitize Tool? > - click on ?Create Feature? > - Make sure you select ?Isochron? as the feature type > - Ensure the Plate ID and Conjugate Plate ID are set to the plateids for the two plates in question (I?m assuming you have this in a rotation file already), and set the appearance time to be the current reconstruction time > - tick the box ?Create conjugate feature' > > Once the feature is created, you should get two lines. They will be exactly superimposed at the current reconstruction, but would move in opposite direction as you move towards present-day. > > This would need to be repeated for each time you want to make isochrons for. > > Cheers, > Simon > > > > >> On 21 Dec 2018, at 11:58 am, Bud Davis wrote: >> >> The very simplest way I?ve done it is to just export a series of ridge shapefiles at each time step your interested in. Set the relative plate to the plate on one side of the ridge, and do the export of the ridge shapefile. Then set to the relative plate on the other side of the ridge. You can easily grid these ridges by assigning them an age and clipping them to the plate you?re interested in in a GIS program. >> >> Cheers, >> >> Bud Davis >> >> On Thu, Dec 20, 2018 at 5:50 PM Mark Brandon wrote: >> Nicky and others, >> Given this discussion about flow lines, it may be useful to ask how one might construct "synthetic isochrons" in GPlates. >> The review paper linked below has a discussion about this idea. >> >> https://protect-au.mimecast.com/s/mVZxCOMxNytkZm0BUEEMZQ?domain=cambridge.org >> >> The objective is nearly identical to producing an grid for plate age. To ask more directly: Is there a simple way to create synthetic isochrons in GPlates? >> Best, >> Mark >> >> > On Dec 17, 2018, at 8:13 PM, Nicky Wright wrote: >> > >> > Hi Mark, >> > >> > At what time are you looking for plate age around the spreading centre? I will admit I haven?t thought about this at all lately. >> > >> > As to why the flowline calculation doesn?t work between 40-29 Ma for your second case (Pacific-JdF): >> > The JdF rotations (plate 910 in the rotation file) are relative to the Pacific plate (plate 901), and have no relative motion with the Pacific plate before 28.3 Ma. >> > >> > To get it to work for the entire time period, you can: >> > ? Create the flowlines for your second case (present-day JdF ridge) using plate 903 (Vancouver) instead - the flowlines will work for the entire time period and will actually use the 910-901 rotations (JdF-PAC) between 0 and 28.3 Ma (this is the easiest option) >> > ? If you?re comfortable editing the rotation file itself and you?d rather stick to plate 910 for your present-day geometry (I know the colour difference in the flowline points might help a little here), you can open the rotation file in a text editor and replace the rotations for 910 with? (I?ve copied from the existing JdF 28.3 Ma rotation from Matthews et al 2016 here): >> > 910 28.3 81.35 -117.91 -30.67 901 !JFC-PAC @REF Wright_++_2016 @DOI"10.1016/j.earscirev.2015.11.015" @CHRONID"c10n1ny" >> > 910 28.3 0.0 0.0 0.0 903 ! JFC-VAN >> > 910 250.0 0.0 0.0 0.0 903 ! JFC-VAN >> > >> > Cheers, >> > Nicky >> > >> > >> > From: GPlates-discuss on behalf of Mark Brandon >> > Reply-To: GPlates general discussion mailing list >> > Date: Monday, 17 December 2018 at 11:44 am >> > To: GPlates general discussion mailing list >> > Subject: [GPlates-discuss] Flow lines and ridge jumps >> > >> > >> > I have been trying out GPlates' flow-line calculation to represent the evolution of the Juan de Fuca spreading center and adjacent plates over the last 40 Ma. As you might know, the JdF spreading center has had some ridge-jump events, one at 20 Ma and another at 5 Ma. My issue here concerns how to represent a change in the spreading center with respect to the flow-line calculation. >> > >> > I document this situation here in two ways, as shown in the two attached movies. The data sources for the reconstructions are: Mueller et al 2016 AREPS Isochrons (Reconstructed Geometries), Matthews et al 2016 GPC, Mesozoic-Cenozoic Plate Topologies (Reconstructed Geometries). The reference frame for the reconstructions is North America fixed, and the time interval is from 40 Ma to present. >> > >> > Note that the Yale email server strips out movie attachments, so the attachments here have extensions of .4pm to avoid this problem. Save the files and then convert the extensions to .mp4, and all will be good. >> > >> > The two reconstructions are: >> > >> > 1) Movie: "flowlines Pacific-Vancouver 40-0 Ma" >> > The 40.1 Ma anomaly on the Pacific plate is set as the left-side endpoint for all flow lines, with the Vancouver plate on the "right side". >> > >> > 2) Movie: "flowlines Pacific-JdF 40-0 Ma.mp4" >> > The modern Pacific/Juan de Fuca boundary is set as a "spreading center", with the flow lines calculated symmetric relative to that reference. (As an aside, I don't know why the flow-line calculation does not work in this case for the time interval between 40 and 29 Ma.) >> > >> > The first reconstruction provides a clear correspondence between the seed points and the coeval spreading center during the early part of the reconstruction. This relationship breaks down after the ridge jumps at 20 and 5 Ma. >> > >> > The second reconstruction shows a poor correspondence between seed point and the coeval spreading center during the early part of the reconstruction. That situation switches to a good correspondence during the later part of the reconstruction. >> > >> > For course, this is all expected given that the seed points for the first case are based on the initial configuration of the spreading center, and the second case, on the final configuration of the spreading center. >> > >> > The first case does a good job representing the motion of the bounding 40.1 Ma isochrons move away from the spreading center. The second case does a good job representing the age distribution near the final spreading center. Both calculations seem to give the same estimate of the displacement field relative to the coeval plate boundary (aka active spreading center). This last point is important, but difficult to precisely verify from these examples. >> > >> > >> It would be useful to hear from the GPlates programmers about this last statement. >> > >> > My objective is not the displacement field, but rather the plate age around the spreading center. My thought at this point is that the plate age might be represented by the minimum of the two age fields. In other words, a ridge jump operates to introducing younger lithosphere in the area around the new ridge. That said, I think there may be some ridge-jump situations that can defeat this simple view. >> > >> > I am hoping to get feedback from others, especially those who have already thought through this situation... >> > >> > Best, >> > Mark >> > >> > >> > >> > >> > _______________________________________________ >> > GPlates-discuss mailing list >> > GPlates-discuss at mailman.sydney.edu.au >> > https://mailman.sydney.edu.au/mailman/listinfo/gplates-discuss >> > _______________________________________________ >> > GPlates-discuss mailing list >> > GPlates-discuss at mailman.sydney.edu.au >> > https://mailman.sydney.edu.au/mailman/listinfo/gplates-discuss >> >> _______________________________________________ >> GPlates-discuss mailing list >> GPlates-discuss at mailman.sydney.edu.au >> https://mailman.sydney.edu.au/mailman/listinfo/gplates-discuss >> >> -- >> Joshua "Bud" Davis >> >> Graduate Research Assistant >> University of Texas-Austin Institute for Geophysics >> buddavis at utexas.edu >> 904-556-4401 >> >> _______________________________________________ >> GPlates-discuss mailing list >> GPlates-discuss at mailman.sydney.edu.au >> https://mailman.sydney.edu.au/mailman/listinfo/gplates-discuss > > _______________________________________________ > GPlates-discuss mailing list > GPlates-discuss at mailman.sydney.edu.au > https://mailman.sydney.edu.au/mailman/listinfo/gplates-discuss