[Users] Loading SEG-Y files with decimal degrees

[G. Diephuis]

Gery et al., 

A small suggestion: convert your spherical coordinates into rectangular ones
using a projection/transformation of choice. Www.bluemarblegeo.com gives
commercial software, from www.hydro.nl you can download free software called
PCTrans

Regards & good luck

Gerhard


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Moral : 

So oft in geologic wars,
The interpreters I ween,
Rail on in utter ignorance
Of what each other mean
And brag about a giant field
Not one of them has really seen!!

Free after John Godfrey Saxe (1816 - 1887)




on 24/11/2008 09:37, Bert Bril at Bert.Bril at opendtect.org wrote:

> Hi Gery,
> 
>> I want to load some SEG-Y lines with decimal degree values as
>> coordinates (sx,sy). How could I load them in OD?. I've recently
>> tried but with no succesful. They are scaled by 10 000. Any hint is
>> very grateful.
> 
> You have the first SEG-Y file I've ever heard of actually using this
> option. Indeed, it's in the SEG-Y standard, but:
> 1) the definition is even harder to understand than the rest of the standard
> 2) In the end, we all work with rectangular coordinates anyway
> 3) If we'd have to support everything described in the standard, then it
> would be even harder for anyone to ever read or write a SEG-Y file
> 
> A I think we're already quite far in supporting all kinds of quirks
> thought up by the 'data managers' that thought up SEG-Y, so we leave it
> to any plugin builder to make the 'perfect SEG-Y' read and write. In the
> mean time, I've now added a warning that we don't support this (which
> will be in the next development release).
> 
> I would try the following:
> 1) You may get away by simply defining a different coordinate scaling so
> that you'd get something that is comparable to meters, sort of.
> 2) See whether there is a processing package (Madagascar?) that can
> process the file and output a SEG-Y file that's more common.
> 
> 
> Regards, Bert