by Nate Hekman on May 1, 2008

The Draw Contours command got a big makeover in version 7.1.  There are two major changes to contours:  saved contours, and contours in Define.

Saved Contours

I’ve mentioned before that version 7 introduced the ability to save graphs, so you don’t have to keep changing the parameters and re-selecting nodes as you explore different aspects of an analysis’ results.

Now Draw Contours gets the same functionality: saved contours.

Version 7.1 allows you to save a list of contour settings

The basic functionality is the same–pick your parameters, ranges and shading options–but now all those properties are saved and given a name, and a simple click on another saved contour in the list will update your drawing.

Contour Toolbar

To simplifiy it more, we’ve also added a Contour Toolbar.  After using Draw Contours to save the contours you want, you can switch between them right from the toolbar.

The Contours Toolbar gives quick access to saved contours.

Contours in Define

Until now the Draw Contours command has always been a way of looking at the results, at the computed data.

With version 7.1, Draw Contours also shows up in the menu in Define, and lets you plot contours of the definition data.

Here’s a SLOPE/W analysis in Define view, showing the pore water pressures it got from its parent analysis.

Contouring input data

This is a very powerful tool to help you determine if you have properly defined an analysis before solving it.  Besides contouring things like pore water pressure, you can also contour material properties such as C and Phi.

{ 25 comments… read them below or add one }


mike jorgensen 05.11.08 at 6:21 pm

Nice addition to contouring. However, I do not see a way to add custom contours or do contouring of concentrations using the log[concentration]. I often want to add a contour corresponding to a contamiant guideline value or see 0.1 mg/L, 1 mg/L, 10 mg/L, etc. I do not see a way to do this.
I tried creating seperate contour intervals (say 0.01 to 0.1 at 0.01 intervals and another set from 0.1 to 1 at 0.1 interval), but I could not plot both at the same time. Any ideas/workarounds?


Nate 05.16.08 at 9:56 am

Thanks for the comment, Mike. I’ve never heard of anyone asking for contours of log values, though that surprises me because it’s a very reasonable request! I’ve logged it as a feature request so hopefully it will show up one of these days.

All I can think of for a workaround is to use an Add-In. Add-Ins can compute their own data which is then available for contouring and graphing. You could likely write an Add-In that simply gets the concentration value, then writes out its log value. Seems like a rather heavyweight solution to what should be a simple problem, but it’s the best I can come up with.

More information about writing Add-Ins is at

I’m not sure what you mean by adding “custom contours”. Can you elaborate?


Rafael 12.11.08 at 10:37 pm

Hi Nate, this is not my original post, but I guess Mike is asking about a possibility of defining our own values for the contours. For example, have contours of only a list of given numbers, let’s say contours of Y-Eff=1, 2, 3, and 5 and 6kPa (Skipping 4kPa).


Nate 12.12.08 at 9:22 am

Good point. I’ll log that as a feature request as well. Seems like a reasonable wish.


siro 06.07.11 at 5:25 pm

I want t see The water surface in embankment ofter the solve in seep/w but I dont know how do it.
guide me pls


Nate 06.08.11 at 11:55 am

I believe what you’re looking for is the Draw Isolines command. Pick the Pore-Water Pressure parameter with a value of 0.0 to see the zero-pressure line.


siro 06.08.11 at 4:47 pm

Tanks a lot Nate for your prior answer.
I have one question again:
what is the difference between The Potential Seepage Face and Zero Pressure hydraulic BC for oblique filter that has a horizontal tail to toe?
which boundary condition applied for this example? Seepage Face for oblique part or Zero Pressure for horizontal tail to toe ?


Nate 06.09.11 at 9:07 am

Ahh, now you’re getting outside of my area of expertise! 🙂 I am not an engineer, so I can tell you how to do something in GeoStudio, but I have no clue which of two options is better from an engineering perspective.

Chapter 5 of “Seepage Modeling with SEEP/W 2007” (available from the GeoStudio Start Page) discusses boundary conditions, including the Potential Seepage Face and Hydraulic BCs. I suggest you read that if you haven’t already. If it’s still not clear, you can email support [at] geo-slope [dot] com, and one of our support engineers will take great pleasure in assisting you.


Dan Klein 12.01.11 at 12:44 pm

Hi there Nate,

When I am putting together contour plots from dynamic analysis, and can’t seem to find how to display the key (legend) of displacements or other values on the side of my plot.




Nate 12.01.11 at 4:33 pm

You can add labels to contour lines using Draw Contour Labels, then clicking on the lines you want to label. That’s not exactly what you’re asking for, but it’s the closest equivalent in geostudio, as there’s no way to automatically create a legend to place on the drawing.

Some people have made their own legend by drawing little rectangular regions floating in the air and assigning them materials whose colours match the contour colours, then using Sketch Text to add text next to them. Not the most intuitive approach, but it works.

Another approach would be to make a legend in some other application, like Word, taking a screen shot of it, and pasting that into GeoStudio as a picture. I’d love to see a real legend feature in a future version.


Dan 02.14.12 at 11:46 am

Thank you Nate,

Yes, I would definitely like to see a legend option in a future version. Without it, one ends up doing a whole lot of explaining and/or cut and pasting for that matter.

On a separate note, I can see how to find the centroid of a slice…but can not seem to locate a way to find the centroid of the sliding mass for a particular factor of safety. Is there a way to do this?

Thank you for the assistance,



Nate 02.15.12 at 10:56 am

@Dan: Under Draw – Slip Surfaces, you get a list of all the slip surfaces and their corresponding factor of safety, as well as the centre and radius in some cases. When your slip surface option is set to Entry & Exit, Grid & Radius, or Auto Locate, you’ll see the centre and radius. When it’s Block Specified or Fully Specified, you won’t. I asked one of our slope specialists why the difference, and his explanation was that because the two “specified” options aren’t really circular, there’s not much value in knowing the centre.


Jon 04.30.13 at 12:13 pm

Dear Nate
I’m a beginner of using Geostudio. In my study, I’m thinking about some of like questions talked above. Sometimes I want to use some results computed with strains, stresses other than themself. But I’m wondering how to get it. Could it need other subroutine to be compiled and embeded into Geostudio? If so, how to do that?
And i have other questions, but i don’t know where i can question them. Here are two:
(1) what the difference between “isolines” and “contour lines” in the post process of viewing results? I’ ve met this in Quake/W analysis (See case lower san fernando dam in the examples, in the cascade of “view / preferences” they could be found) sometimes the results is weird when isolines is choosen.
(2)when i use multipurpose analysis( SeepW+ SlopeW+ SigmaW+Quake, like case of San Fernando dam, the case is no problem when being computed), the case set up by myself can be computed successfully forSeepW+ SlopeW+ SigmaW, but to QuakeW, it failed to solve! It tells ‘Zero on diagonal of global property matrix at equation No. XXXXX, value=0’. I want to know what the reason is. Could some guys help me check it out? If needed, i can send the data of case to be checked.



Nate 06.26.13 at 3:47 pm

Jon, I’m so sorry for the late reply. I just noticed that my comment notifications were going to a spam box that I don’t check often. 🙁

You have already contacted me by email and we worked through some of these issues, but I’ll leave a response here too for others to find who might have similar problems.

I’m not sure I understand your question about using computed stresses and strains. You can create a “child” analysis that gets its initial stresses from a “parent” analysis.

For your other questions:
(1) “Contour lines” and “isolines” are very similar. The main difference is that contour lines show how a parameter varies across the domain at a single moment in time, whereas isolines show how a specific value varies over time. For example, an isoline can show you how the water tables (pwp=0) moves over time, whereas contour lines would show you at one moment in time how the pwp is distributed over the area.
(2) We’ll have to see your .gsz file to understand what’s happening here. You can send it to support [at] geo-slope [dot] com.



Guillermo 09.15.13 at 9:47 pm

when i use QuakeW, it failed to solve! It tells ‘Zero on diagonal of global property matrix at equation No. XXXXX, value=0′. I want to know what the reason is. Could some guys help me check it out? If needed, i can send the data of case to be checked.


Nate Hekman 09.23.13 at 8:53 am

Hi Guillermo. I’m not sure what that would mean. It’s probably best if you send the .gsz file to support [at] geo-slope [dot] com to have an engineer take a look.



Nadezhda 06.01.15 at 1:31 am

Hi, Nate!
I need to view contour (stresses) only in one region from the entire problem. Can you help me with the advice how to make it?
Thank u


Nate Hekman 06.02.15 at 1:17 pm

@Nadezhda: That’s not something GeoStudio supports. Contours always display across the entire geometry.

What is the usage case? Why do you feel the need to only show stresses in one region? I may be able to suggest an alternative approach, or consider adding this as a new feature, if I can understand the situation.


Nadezhda 07.08.15 at 5:51 am

@Nate. I have some analysys like tunnels in ground and I need to see stresses only in concrete lining


Nate Hekman 07.13.15 at 11:54 am

@Nadezhda: Thanks. I’ll talk to our engineers and we’ll think about how we could offer such a feature. Thanks for the suggestion.


Jose 09.14.15 at 8:26 am

Hi Nate.
I have the same problem of Guillermo and Jon (in Quake/w). A error message appears saying “zero on diagonal of matrix”.
Please, could you tell me what is the reason?


Nate Hekman 09.14.15 at 8:40 am

@Jose: Send your .gsz file in to support [at] geo-slope [dot] com and explain to them what is happening, and one of our engineers will take care of it with you. That error message is beyond my knowledge of the software!

But since you’re the third person on this blog to ask it, it would probably be useful to make the answer public! After you get a satisfactory answer from support, can you come back here and post an answer?


Oli 06.03.18 at 5:27 pm

HI Nate,
I have the same problem “Zero on diagonal of matrix in GeoStudio 2018”. Is there a solution that your team found in 2015 and could make public? FYI, GeoStudio error messages are really not usefull. There is never an easy way of knowing what’s wrong.
Thanks for the help.


Nate Hekman 06.04.18 at 8:43 am

@Oli: I agree that error is rather unhelpful. Unfortunately it is outside my area of expertise. You should open a support ticket at (scroll to the bottom and click “Submit a Support Request”). As I encouraged Jose, please do report back here with the solution, or some troubleshooting steps!


Imad Habeeb 03.25.19 at 10:57 am

Hi Nate …
How can I extract free surface points data, i.e. (x,y) pairs per each point on the free surface for a steady or/and sudden drawdown states?
Thanks for the help.
Imad H. Obead

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