Abscissa and ordinate Abscissa and ordinate In mathematics, the abscissa (; plural "abscissae" or "abscissæ" or "abscissas") and the ordinate are respectively the first and second coordinate of a point in a coordinate system. The abscissa of a point is the signed measure of its projection on the primary axis, whose absolute value is the distance between the projection and the origin of the axis, and whose sign is given by the location on the projection relative to the origin (before: negative; after: positive). The ordinate of a point is the signed measure of its projection on the secondary axis, whose absolute value
Paired metamorphic belts Paired metamorphic belts Paired metamorphic belts are sets of parallel linear rock units that display contrasting metamorphic mineral assemblages. These paired belts develop along convergent plate boundaries where subduction is active. Each pair consists of one belt with a low-temperature, high-pressure metamorphic mineral assemblage, and another characterized by high-temperature, low-pressure metamorphic minerals. The concept of paired metamorphic belts was originally theorized by the Japanese geologist, Akiho Miyashiro in 1961. The parallel arrangement between the metamorphic belts and the similar ages of each belt, led Miyashiro to the idea that metamorphic belts formed together as pairs. The introduction of the paradigm