Danupon Tonnayopas, Somchai Chaisen and Kalayanee Kooptarnond

pp. 675 - 700

Abstract

An investigation of potential building sand deposits in Songkhla province area subdivided them
into four regions according to their accumulation in various alluvial plains, meanders throughout alluvial
deposits and residual soils. Four selected deposits, were Rattaphum-Khuan Niang, U-Taphao river,
Na Mom, and Chana-Thepha regions. Information obtained from these deposits revealed a good correlation between the geomorphological features as interpreted from aerial photographs and those identified
from vertical electrical resistivity sounding results. Sand samples were analysed for their physical and
chemical properties. Petrographic studies were also undertaken to characterize the composition types, texture and shapes. An overview of the sand properties was used them to be within the acceptable limits
for building sand. However, relatively high organic impurities and soundness were found in sand from
Khuan Niang and Na Mom deposits. The result indicated a potential reconnaissance mineral resource
of about 46 square kilometres.
A reserve evaluation for natural building sand was carried out by using Geographic Information
System (GIS). Maps of the various parameters considered were constructed in digital database format
with the aid of Arc/Info and ArcView software. Overlay mapping and buffer zone modules were performed
to evaluate inferred resources of building sand. The key parameters of analysis included the distance
from transportation, distance from streams, lithology and thickness of sand layers. The remaining
inferred sand total was of about 386 million cubic metres or about 1,021 million metric tons was therefore
estimated, of which 60 percent lies in the Rattaphum-Khuan Niang region and 40 percent in the other
regions.

Keywords

• Engineering geology
• sand deposit
• Songkhla
• GIS
• geoelectric
• buffer zone
• overlay mapping