Hi, Maybe some ideas :
Le 10 Feb 2011 à 05:43, Stacho Mudrak a écrit : > Hi all, > > we are solving a problem of adding a basic geological observations > (measurements) to therion. > When measuring a planar feature (bedding or fault or others), you > measure strike and dip. > When measuring linear features, trend and plunge is measured. > In the case of faults, also whether it is dextral or sinistral fault > is determined and potentially a magnitude. > > My question is, do you have some idea/wish how to integrate these > into therion? I have some experience with that as sometime I do geological/ microtectonic field work. 1) The easiest way I found to write these informations on a map and/or field book, this is to write as you wrote a T (for planes) oriented in regards to the strike. I am used to write the strike on the side of the T, and the dip at the base of the T. For linear features, I just draw a line oriented in regards to the trend, with a point at the starting af the direction. I also write trend and plunge. I attach to this email an example of what that gives. For faults, this is a plan. When they are lines on the plan, I add a line inside the T, in regards to the side of where it plunges, and I write the value of the plunge. To say if it is a normal, inverse, dextral and/or senestral fault, one idea is maybe to write a N, I, D, S, ND, NS, ID or IS just above the T. 2) Another possibiliy to show these features is to use stereographic projections (Wulf or Schmidt diagrams), as it is usually done in publications (ex : http://en.wikipedia.org/wiki/File:StereoprojectStructuralgeol.jpg) . BUT, that means that a routine should be written to produce the projections. And, for someone that is not used to work with these data, this is very hard to read/understand. Thus, I would prefer the first solution. > Do you have some experience with it? > > Our first idea is to add a standard T symbol for strike and dip > measurement, but there is one problem. Orientation of this symbol is > not drawn, but it is measured (with compass). But its position is > given by position on the map. Should these measurements be entered > into a table (as centerline data are), or put as options with symbols? I do not know if it possible, but I think that for me it would be easier to use this symbol with options, something like : for a plan/fault : -plan "Strike" "Dip" -fault "type" - line "Plunge" (with type = N or I or D or S or ND or NS or ID or IS) for a line : -line "Trend" "Plunge" From that, you build the symbol (T/line+values) and then from the Strike or the Trend, you rotate the symbol. If that helps, that's great ! Cheers, Xavier > > Do you have any ideas or comments? > > Best regards, S. > > > > > _______________________________________________ > Therion mailing list > Therion at speleo.sk > http://mailman.speleo.sk/mailman/listinfo/therion -- Xavier ROBERT CIFAR Junior Fellow GEOTOP, Département des Sciences de la Terre et de l'atmosphère Université du Quebec a Montréal CP 8888, Succursale centre-ville MONTREAL, Quebec H3C 3P8 (1-514) 987-3000 poste 3592 xavier.robert01 at gmail.com http://www.geotop.ca/index.php?option=com_content&task=view&id=861&Itemid=148 http://www2.cifar.ca/research/junior-academy/cifar-junior-fellows/?i=331 http://picasaweb.google.com/xavier.robert01 -------------- next part -------------- A non-text attachment was scrubbed... Name: microtectonicsex.pdf Type: application/pdf Size: 209744 bytes Desc: not available URL: <http://mailman.speleo.sk/pipermail/therion/attachments/20110210/3419f300/attachment.pdf> -------------- next part --------------
