Lab 1: Terrain Survey

Introduction

            To demonstrate many of the concepts of geospatial thinking such as terrain analysis, this lab aims to demonstrate how to create a map of a unique elevation surface using a homemade coordinate system and survey technique tailored to the fit the parameters of the target natural surface surveyed.

Methods

            To survey the planter box assigned to us in the Phillips court yard, a coordinate system covering the 42 x 84 inch area of interest of the planter box using six by six inch grid cells was established using string fastened to the upper rim of the planter box with the origin as the bottom left hand corner of the box. Once the x, y coordinate system of grid cells was created, we then set out to record the z component of each grid cell by measuring down from the center of each six by six inch cell from the established “sea level” plain created by the string to capture the relief of the terrain. Although these numbers are theoretically negative in value, a simple equation will be created to reverse that when importing the collected data into ArcMap.

 

Discussion

            As with all field work, there is always unpredictable conditions that may be encountered. Aside from subzero conditions, our group experienced issues with data collection right from the get go. When setting up our devised grid system of string, we found that the electrical tape brought to secure each end down to the rim of the box would not stick to the wood due to such cold temperatures. To work around this issue, we cut notches into the rim of the planter using a pocket knife to permanently define the six inch intervals, and then used a yard stick to create temporary edges to each grid cell surveyed when taking the z coordinate measurements. Although this method took much more time which led to near frostbit fingers, the same result was created as would have been done with the permanent grid defined by string.

Conclusion

            After completing our first run at this lab, a few conclusions and observations can be drawn. First, when we do this again, we will use tacks to secure the string to the edge of the box to account for tape not working in cold temperature. Also, a finer network of three inch by three inch grid cells will be created to allow for a higher resolution map of the surveyed terrain because our six by six grid was far too course.