3.7.8 Dome (Dom)
3.7.8.1 A dome is a positive geomorphological and/or structural form element which is defined by having a regularly curved surface. In horizontal section a dome has an approximately circular or elliptical outline. The structure is usually not bounded by faults (Figs. 9, 10).
3.7.8.2 Every dome can be classified as a high.
3.7.8.3 No limitations are placed on the dimensions of a dome.
3.7.8.4 Domes are mappable with the help of geomorphological, geological and/or geophysical methods.
3.7.8.5 Domes may often be divided into smaller geomorphological and/or structural elements. If the structure is more long and narrow, rather than circular, in outline, the term arch is appropriate (Section 3.7.9.7.c).
3.7.8.6 A dome can be given a formal or an informal name in accordance with the "general rules for naming and defining geological units" (Chap. 2) and the rules for naming geological form units (Section 3.7.1). In formal compound names, a proper name (Section 2.2.2) is placed between the words "the ... Dome". If a dome is recognized as being a structural or geomorphological dome this can be indicated by, for example, "structural dome", "salt dome" or "volcanic dome".
3.7.8.7.a A structural dome need not be, or have been, a landform.
3.7.8.7.b A diapir is a dome or an anticlinal fold in which the arching process has led to the overlying rocks being pierced by plastic material squeezed from the core of the diapir.
3.7.8.8 Example: The Gjersøen dome is a structural dome in the Precambrian basement east of Oslo (Zetterstrøm 1974).
3.7.8.9 Key reference: Bates & Jackson (1980).
