The temporal topology schema for ISO19136 provides constructs for handling topological complexes and temporal feature relationships. Temporal geometric characteristics of features are represented as instants and periods. While, temporal context of features that does not relate to the position of time is described as connectivity relationships among instants and periods. These relationships are called temporal topology as they do not change in time, as long as the direction of time does not change. It is used effectively in the case of describing a family tree expressing evolution of species, an ecological cycle, a lineage of lands or buildings, or a history of separation and merger of administrative boundaries. This schema reflects a partial yet consistent implementation of the model described in ISO 19108:2002. Copyright (c) 2002-2005 OGC, All Rights Reserved. For conditions, see OGC Software Notice http://www.opengeospatial.org/about/?page=ipr This element represents temporal topology complex. It shall be the connected acyclic directed graph composed of time nodes and time edges. A temporal topology complex. A time topology complex property can either be any time topology complex element encapsulated in an element of this type or an XLink reference to a remote time topology complex element (where remote includes elements located elsewhere in the same document). Note that either the reference or the contained element must be given, but not both or none. This abstract element acts as the head of the substitution group for temporal topology primitives. The element "complex" carries a reference to the complex containing this primitive. A time topology primitive property can either hold any time topology complex element eor carry an XLink reference to a remote time topology complex element (where remote includes elements located elsewhere in the same document). Note that either the reference or the contained element must be given, but not both or none. "TimeNode" is a zero dimensional temporal topology primitive, expresses a position in topological time, and is a start and an end of time edge, which represents states of time. Time node may be isolated. However, it cannot describe the ordering relationships with other primitives. An isolated node may not be an element of any temporal topology complex. Type declaration of the element "TimeNode". A time node property can either be any time node element encapsulated in an element of this type or an XLink reference to a remote time node element (where remote includes elements located elsewhere in the same document). Note that either the reference or the contained element must be given, but not both or none. TimeEdge is one dimensional temporal topology primitive, expresses a state in topological time. It has an orientation from its start toward the end, and its boundaries shall associate with two different time nodes. Type declaration of the element "TimeEdge". A time edge property can either be any time edge element encapsulated in an element of this type or an XLink reference to a remote time edge element (where remote includes elements located elsewhere in the same document). Note that either the reference or the contained element must be given, but not both or none. Feature succession is a semantic relationship derived from evaluation of observer, and Feature Substitution, Feature Division and Feature Fusion are defined as associations between previous features and next features in the temporal context. Successions shall be represented in either following two ways. * define a temporal topological complex element as a feature element * define an association same as temporal topological complex between features.