Data integration using fuzzy operators using standard rules of fuzzy algebra one can combine various thematic data layers, represented by respective membership values (Chung and Fabbri, 1993).

Example: In a grid cell/pixel if a particular litho-unit occurs in combination with a thrust/fault, its membership value should be much higher compared with individual membership values of litho-unit or thrust/fault. This is significant as the effect is expected to be "increasive" in our present consideration and it can be calculated by fuzzy algebraic sum. Similarly, if the presence of two or a set of parameters results in "decreasive" effect, it can be calculated by fuzzy algebraic product. Besides this, fuzzy algebra offers various other methods to combine different data sets for landslide hazard zonation map preparation. To combine number of exploration data sets, five such operators exist, namely the fuzzy AND, the fuzzy OR, fuzzy algebraic product, fuzzy algebraic sum and fuzzy gamma operator.

Fuzzy logic can also be used to handle mapping errors or uncertainty, i.e. errors associated with clear demarcation of boundaries and also errors present in the area where limited ground truth exists in studies such as landslide hazard zonation. The above two kinds of errors are almost inherent to the process of data collection from different sources including remote sensing.

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