A CONVERSION TOOL FOR OUTPUTS OF STANFORD GEOSTATISTICAL MODELING SOFTWARE TO ARCGIS

The Stanford Geostatistical Modeling Software (SGeMS) was developed at Stanford University and implements geostatistical algorithms for modeling earth systems. It has a software interface which provides the user with access to the most common geostatistic tools as well as more advanced and recently developed algorithms. Results of these tools can be visualized interactively in two- or three-dimensions. The tools can also be executed outside of the user interface, programmatically, via integrated Python support. This allows for the creation of macros and even complete applications, which tie into the SGeMS API. The integration of two- and three-dimensional visualization in the field of geostatistics is crucial to better understand geological data and being able to seamlessly move from one visualization application to another is essential. Unfortunately, some of the data exported from SGeMS cannot be imported easily into ArcGIS, as coordinate systems in ASCII form are not easily transferred into other GIS systems unless they are formatted correctly.

SGeMS is designed to output data in the GSLib-file format as an ASCII text file. ArcMap and ArcGIS Pro allow the import of ASCII data, but the formatting of GSLib files differs from the ESRI format. As such, it is necessary to transform the data to adhere to the ESRI ASCII raster format specifications. GSLib differs in that each cell is read from left to right starting at the southwest corner, advancing to the north, while the ESRI-grid format reads from left to right, starting in the northwest corner, and advances to the south. This difference in grid organization causes the data to be loaded in the wrong order, and subsequently in the wrong orientation.

To alleviate this problem, the SGeMS Conversion Tool was created to import SGeMS maps and their derivatives into ArcGIS with a single tool composed of a Python script written for ArcGIS. The script is designed to take output from SGeMS and process the data into a format which can then be imported into ArcGIS, where further analyses may be conducted. To test the effectiveness of the algorithm in allowing users to convert data into the correct format, multiple datasets provided by the USGS were used (copper density in fine and course grid forms) and the tool proved successful in reducing the amount of manual work required to accomplish this task.