The question asks about mapping techniques used to show clearly defined or delineated areas, where each area is assigned a different colour. Let's examine the options provided to determine which technique fits this description.

Understanding Different Mapping Techniques

Mapping techniques are methods used in cartography (mapmaking) to represent geographical data visually on a map. The choice of technique depends on the type of data (quantitative or qualitative) and how it varies across space (continuous or discrete areas).

Here's a brief overview of the techniques mentioned:

• Isopleth Map: This technique is used to represent continuous data, meaning the data exists everywhere, not just in specific areas. Examples include elevation, temperature, or air pressure. Lines (isopleths) are drawn connecting points of equal value, and the areas between these lines are often shaded or coloured based on the data values. It doesn't primarily deal with distinct, pre-defined areas using different colours for qualitative differences.
• Choropleth Map: This technique represents quantitative data within defined administrative or statistical areas (like countries, states, or counties). The areas are shaded or patterned in proportion to the statistical variable being displayed (e.g., population density, income level). Darker shades usually represent higher values. While it uses colour or shading in delineated areas, the colour is tied to the *magnitude* of a statistical variable, not just used to distinguish different types of areas with unique colours.
• Chorochromatic Map: This technique is used to show the spatial distribution of qualitative data by assigning different colours to distinct areas based on their category or type. These areas are clearly delineated (have sharp boundaries). Examples include maps showing soil types, geological formations, vegetation zones, or land use categories. Each distinct category is represented by a specific, different colour. This perfectly matches the description of "delineated areas having different colours" where the colour indicates the *type* of area.
• Choroschematic Map: This technique uses symbols within defined areas to represent the characteristics or features of those areas. The symbols are often schematic or simplified representations of the features. An example might be using different symbols to show the dominant industry in various towns on a map. It doesn't typically involve filling the entire delineated area with a distinct colour for qualitative categorization.

Analyzing the Options Based on the Description

The question specifically mentions "delineated areas having different colours". Let's see which technique aligns best:

Based on this analysis, the Chorochromatic mapping technique is specifically designed to show delineated areas that represent different categories or types using distinct colours.

Conclusion

The mapping technique that is correct to show delineated areas having different colours, where the colour distinguishes the type or category of the area, is Chorochromatic. This method is ideal for representing qualitative spatial data with clear boundaries.

Revision Table: Key Mapping Techniques

Additional Information on Thematic Mapping

The mapping techniques discussed (Isopleth, Choropleth, Chorochromatic, Choroschematic) are all types of thematic maps. Thematic maps are maps that focus on illustrating the spatial distribution of a specific theme or topic, rather than just showing geographical features.

• Qualitative Data: Data that describes categories or types (e.g., land use type, political affiliation, language spoken). Chorochromatic and Choroschematic maps are often used for this.
• Quantitative Data: Data that represents numerical values or quantities (e.g., population density, rainfall amount, average income). Isopleth and Choropleth maps are commonly used for this.
• Understanding the type of data you have and the spatial pattern you want to show is key to choosing the right mapping technique in cartography.