Previous versions of Thema are still available 1.3 1.2 1.1 1.0.
Browse the Thema subject categories hierarchy, or search for a specific term within the hierarchy.
| Notation | Category heading | Add | Mod | ? |
|---|---|---|---|---|
| R | Earth Sciences, Geography, Environment, Planning Use all R* codes for: academic, technical, specialist and general adult titles. DO NOT USE: code ‘R’ itself, but select specific categories from section R*. Use all R* codes with: other subject categories and qualifiers where appropriate, in particular PLACE 1* Qualifiers |
1.4 | ✽ | |
| RB | Earth sciences Use all RB* codes for: academic, specialist and professional level works. Prefer: WN* codes for the general reader. See also: RGB* Physical geography and topography and its subcategories, WN* Nature and the natural world: general interest and its subcategories |
1.3 | ✽ | |
| RBG | Geology, geomorphology and the lithosphere See also: PHVG Geophysics, RGB Physical geography and topography |
1.2 | ✽ | |
| RBGB | Sedimentology and pedology See also: PNC Environmental chemistry, TNCC Soil and rock mechanics, TVBP Soil science and management |
1.2 | ✽ | |
| RBGD | Geomorphology and geological surface processes Class here: erosion, deposition, glaciology, fluvial and aeolian processes etc. See also: RGB Physical geography and topography |
1.2 | ✽ | |
| RBGF | Historical geology and palaeogeology Class here: plate tectonics, continental drift, past supercontinents, such as Pangaea, Gondwana, Laurasia, the geological history of the Earth, etc |
1.4 | ✽ | |
| RBGG | Petrology, petrography and mineralogy | 1.2 | ||
| RBGH | Stratigraphy | |||
| RBGK | Geochemistry See also: PNC Environmental chemistry, PNV Chemistry of minerals, crystals and gems |
✽ | ||
| RBGL | Economic geology Class here: petroleum and mining geology |
✽ |
version detail
- An ellipsis indicates a category has more detailed subcategories
- Click on a category description to reveal these ‘descendant’ subcategories
- Indentation indicates the ancestors and descendants of a category
- Click on the ✽ or ? to see or hide the usage notes
- Search for categories (for example ‘celebrity’) using the search field at the top
- Searches are not case-sensitive, and search both the category headings and any notes
- You don’t need to use complete words (eg ‘celeb’)
- You can also search for Thema codes – these searches must be exact (eg ‘MFGV’)
- Click on a search result category to see it ‘in context’ with its ancestor and descendant categories
- A click on ‘Category heading’ or a blank search returns you to the top level of the hierarchy
- Click on the notation to copy the code to the clipboard