Description

The forces and processes leading to a large structural deformation of the Earth's lithosphere due to the movement of tectonic plates resulting in the formation of mountains and related geomorphological features (e.g. intermontane basins). Orogeny typically occurs over time periods of millions of years. Orogeny generally occurs at tectonic plate margins where different plates are in contact and is associated with crustal deformation, faulting, folding and subduction and resulting seismicity and magmatic/volcanic activity.

Category

Categorisation as a Feature, Event and/or Process.

  • Features are physical components of the disposal system and environment being assessed. Examples include waste packaging, backfill, surface soils. Features typically interact with one another via processes and in some cases events.
  • Events are dynamic interactions among features that occur over time periods that are short compared to the safety assessment timeframe such as a gas explosion or meteorite impact.
  • "Processes" are issues or dynamic interactions among features that generally occur over a significant proportion of the safety assessment timeframe and may occur over the whole of this timeframe. Events and processes may be coupled to one another (i.e. may influence one another).

The classification of a FEP as an event or process depends upon the assessment context, because the classification is undertaken with reference to an assessment timeframe. In this generic IFEP List, many IFEPs are classified as both Events and Processes; users will need to decide which of these classifications is relevant to their context and its timeframes.

  • Process

Relevance to Performance and Safety

The “Relevance to Performance and Safety” field contains an explanation of how the IFEP might influence the performance and safety of the disposal system under consideration through its impact on the evolution of the repository system and on the release, migration and/or uptake of repository-derived contaminants.

Orogeny is a consequence of tectonic movements (FEP 1.2.1) and its potential influences on repository performance and safety are similar to those described for tectonic movements (FEP 1.2.1). ‘Orogeny’ is associated with crustal deformation, faulting, folding, sub- and obduction and resulting seismicity and magmatic/volcanic activity. In the post-closure period these processes may affect: the general environment of a repository (e.g. distance from the ocean, elevation above sea level, climatic conditions); the proximity of a repository to the ground surface; the potential for damage to waste containers and engineered barriers within a repository, and/or to the surrounding geosphere, as a result of active faulting or magmatism; the forces driving movements of groundwater, other liquids and gases from and around a repository; and the thermal gradients in the geosphere surrounding a repository.

2000 List

A reference to the related FEP(s) within the 2000 NEA IFEP List.

1.2.01

Related References