Scope of Remote Sensing in Natural Resources Survey

Scope of Remote Sensing in Natural Resources Survey

The wealth of mankind largely depends on the application of science to the production and transformation of natural resources useful to man. In the past, this wealth was heavily dependent on agriculture and agricultural products, and in many parts of the world, it still is. However, in modern times, fundamental industries such as iron and steel, other metals, cement, fertilizers, petroleum, coal, atomic mineral products, metal products, transportation vehicles, electrical goods, and electronic equipment play a decisive role in maintaining high living standards.

In advanced countries, these fundamental industries are often based on agriculture, but they are also heavily reliant on the presence and use of mineral products. Therefore, surveys for mineral resources must be prioritized in the economic planning of any country, especially developing ones. The importance of raising food production and better utilizing natural resources, including minerals, forests, soils, surface and groundwater, and other natural resources, cannot be overstated.

The search for water through hydrological studies of the Earth’s surface is particularly important, alongside forestry and agriculture, and in some cases, industry. The search for mineral resources is a specialized subject as the fundamentals of mineral economics differ significantly from other industries. In this context, remote sensing techniques using aerial photographs and satellite imagery for geological investigations offer vast possibilities for specialization. Remote sensing is a crucial tool for efficiently investigating a country’s potential, significantly contributing to the knowledge of terrain regarding geology, rocks, minerals, soil, water, and vegetation.

India, one of the largest countries globally, is endowed with abundant natural resources, though much of this wealth remains unexploited. Geological resources, including metallic and non-metallic mineral deposits, radioactive minerals, fuel minerals, surface and groundwater resources, and various geological parameters for engineering projects, constitute a significant share of this natural wealth. These resources play a vital role in the country’s economic development, which relies heavily on reliable surveys, scientific assessment, and proper utilization of this natural wealth.

However, one of the major challenges in realizing the full benefits of these resources is the improper exploration and exploitation of minerals and other earth resources. The combination of remote sensing techniques via airplanes and satellites with geophysical surveys has revolutionized geological exploration. Remote sensing has provided a macroscopic synoptic view in multiple bands of the electromagnetic spectrum, a capability that was inconceivable just two decades ago. This advancement has allowed for new structural and geomorphological interpretations and mineralization postulations across the Earth’s surface.

New morpho-tectonic theories have been superimposed on earlier metallogenic maps, leading to new conceptual models of mineralization based on a clearer understanding of the actual structures and geomorphology involved. This has facilitated the upgrading, if not the complete revision, of geological and mineralization maps for vast regions of the country through remote sensing data analysis from air and space platforms. Additionally, the seasonal repetitive nature of satellite imagery has proven tremendously advantageous for geological and mineral mapping, enhancing the accuracy of mapping geological formations and mineral deposits.

Application of Remote Sensing in Various Natural Resources

1. Mineral Resources

Remote sensing, particularly aerial photo-interpretation, has been immensely valuable in mineral prospecting and exploration surveys. Many developing countries still rely on slow, conventional ground exploration techniques, with vast areas remaining inaccessible due to a lack of roads and communication lines. In such regions, aerial photo surveys, combined with satellite imagery and geophysical surveys, have shown phenomenal economic potential.

Many geological projects worldwide have demonstrated that remote sensing techniques from air and space have led to significant improvements in understanding the geology and mineral potential of the areas studied. These techniques have revealed new mineral locations, oil fields, and structures, providing enormous information on new lineaments, fractures, faults, intrusives, and other structural features associated with minerals and oil deposits.

Geological structures in rocks play a crucial role in controlling the occurrence of solid and liquid minerals (water and oil). Delineating major folds, faults, fractures, fissures, quartz reefs, dykes, and other intrusives significantly impacts mineral occurrences, groundwater potential, and the assessment of ground suitability for various engineering projects. Aerial photographs clearly display these features, offering a stark contrast to time-consuming conventional techniques.

2. Groundwater Surveys

Due to erratic rainfall patterns, groundwater prospecting and exploration have become significant challenges in India, particularly in drought-stricken areas. Photo-interpretation of aerial photographs and satellite imagery on different MSS bands has proven valuable in providing essential data for assessing a region’s groundwater conditions. This data includes the nature and distribution of vegetation, soil moisture, drainage patterns and density, and seasonal variations.

Additionally, remote sensing provides information on rock types, structural attitudes, geomorphological relationships, faults, fractures, fissures, major drainage controls, shifts in spring lines, and variations in water levels in surface water bodies. Identifying gravels, sands, and alluvium in river valleys and other water-bearing rock formations in hard rock terrains helps locate groundwater sources. The success of groundwater drilling depends entirely on prospecting and exploration data obtained by field surveyors, which can be significantly enhanced by remote sensing techniques.

3. Geotechnical Investigation

Photo-interpretation techniques are extensively used in geotechnical surveys for major engineering projects, particularly in studying the geology, morpho-tectonics, and seismo-tectonics of dam sites and their reservoirs. Remote sensing can maximize the utilization of India’s surface water potential by identifying possible dam sites and addressing flood control problems. Photo-geological techniques are essential for studying various geological aspects across different parts of India.

4. Soil Survey

The primary aim of soil surveys is often agricultural development, though they are also used in town planning and construction work. In agriculture, ecological and agricultural conditions are crucial. Data on soil qualities, surface and groundwater availability, oxygen and nutrients for crops, and soil erosion resistance are key criteria for assessing soil suitability for various uses.

One task of soil surveys is to identify the best farming land—land with high fertility, good drainage, and sufficient moisture. Photo-interpretation and remote sensing are invaluable for other soil-related aspects, including soil conservation, agricultural planning, farming types, crop rotation, and plant disease distribution and control.

5. Forest Inventories

Modern techniques such as aerial photography, photogrammetry, and satellite imagery are critical tools for forest management. These tools enable rapid, accurate, and efficient forest inventory procedures, which include mapping forests, measuring tree and strand qualities, stem diameter, aerial distribution, species percentage, age classification, insect and disease surveys, road location, fire protection, recreation, and wildlife management.

In conclusion, photo-interpretation and remote sensing have already proven extremely useful to foresters in the western world and should also be adopted by developing countries.