Bulletin : 2002 / #01

A study of spatial distribution of beach minerals in the Gulf of Manner

Introduction
Geographic Information System or GIS offers an incredibly useful way to deal with many of the complex decisions. In practical terms, GIS offers a variety of analysis and modeling tools for examining, analyzing and interpreting the relevant data. A GIS as a decision

support system is thus a computer software technology that combines attribute data as well as spatial data - vector, raster, CAD, and TIN - with statistical analysis to evolve a variety of scenarios for exploration and development.

Professionals and decision makers, who are specialists in their fields, but who do not necessarily have any spatial analysis backgrounds, use GIS, increasingly. As a result, GIS is rapidly emerging as an essential decision support tool of government agencies, utilities, educational institutions, and private and public corporations. What follows is an abstract of a study carried out to demonstrate the application of GIS in comprehending the distribution of occurrence of minerals in beaches along the Gulf of Mannar, in South India. The study was carried out at the instance of Professor, N.C. Chandrasekar, of VOCC, Tuticorin, Tamil Nadu, and was helped by his research scholar, Mr Anil Cherian.

The study
VOCC had collected data on occurrence of 12 selected beach minerals at 9 locations along the Gulf of Mannar. For the purposes of this study I "interpolated" data for another 13 locations.

I created a digital map with all 22 locations as geo referenced vector points. I created 12 attribute database tables - for 12 beach minerals - of text and numbers as field types for 22 records representing information of magnitude of occurrence of minerals. I have created 12 digital elevation models - one model for one mineral - of the study area covered by 22 locations to see the distribution of occurrence of beach minerals qualitatively as well as quantitatively. I have also created pin maps representing volume of occurence of beach minerals at each location.

GIS routines I performed for the study, included scanning a paper map of the area, importing the scanned map into the GIS software, geo referencing the imported scanned map, removing the residual error, spatial data editing, creating the attribute databases, attaching the databases with one another and the spatial data, creating a digital elevation model for each mineral using the field data, creating a pseudo color table for each of the models, creating a land use map based on the information available from the secondary sources, and overlaying the digital elevation models on land use map. I have created a total of 12 digital elevation models. I have used TNTmips software for the entire study.

Results of the study
I have created a land use map of the area from the information available from secondary sources. When I display this map along with the digital elevation model of distribution of occurrence of beach minerals we can clearly comprehend the land use scenario on the surface against the geological scenario of the subsurface. If we overlay the "classified" IRS LISS III data on the prevailing overlay of land use map and digital elevation model, we shall be able to identify more of the potential locations for explorations. The study may thus help in pinpointing the locations for optimum commercial explorations of beach minerals on time and within budget.

Comments
The study is not exhaustive. Yet it demonstrates a way to conduct a more credible study of the availability of beach mineral resources in the Gulf of Mannar on time and with a small budget.

Consultative approach of Physical Planning Consultants India Limited goes far beyond the convention. At Physical Planning Consultants India Limited, the approach depends heavily on service. We present ourselves as servicepersons serving as researchers for our clients, making sure our clients have everything they need that we can supply

For information on academic collaboration on urban / rural / renewable energy / GIS development projects, contact us at ppcil@stormloader.com

Dilip Kumar Paul.
January 15, 2002.

Case Study / GIS / 2002 / 01