Characteristic of taveners choral works is the presence of and harmonies based on greek orthodox that avoid the progressions of major or minor harmony and create an almost static effect

drones, modes

Explanation:

In order to know more about the answer, let's get to know who John Tavener is.

John Tavener- He is an English composer who is known for his extensive output of religious works. He converted to the Russian Orthodox Church in 1977. He also had a subsequent experience of the Russian and Greek culture. This is the reason why much of his work has been influenced by Orthodox theology and liturgical traditions.

Tavener's choral works is characterized by the presence of drones and harmonies. A drone is a harmonic and monophonic effect or accompaniment. The note or chord in here is continuously sounded throughout most or all of the piece. On the other hand, a harmony refers to the simultaneously occurring frequencies, pitches or chords. The drones and harmonies in Tavener's choral works are based on Greek Orthodox modes. Mode, in music, refers to the ordering of the notes of a scale according to intervals. Greek Orthodox mode avoids progressions of major and minor harmony. This creates an almost static effect, which is stationary or fixed.