Gemination at the junction of phonetics and phonology

Laboratory Phonology 10 Tashlhiyt Berber has contrastive singleton and lexical geminate consonants in all positions. In
addition, it has two types of phonologically derived geminates: concatenated and assimilated
ones. Within CV phonology, geminates, including post-lexical ones, are represented as single
melodic units associated to two prosodic positions. This study examines the way these
abstract autosegmental representations are reflected in the phonetic details of speech
production. In particular, it investigates two questions: what are the acoustic and articulatory
differences between singletons and lexical geminates; and are there any acoustic differences
between the three types of geminates. Results show that the primary correlate which
distinguishes singletons from geminates is duration, even for voiceless stops after pause. This
primary correlate is enhanced by additional correlates which are crucial to perception of
absolute initial and final geminates. The comparison between the three types of geminates
shows that they all display the same temporal values which supports the assignment of the
same timing representation to these three types of geminates. However, while assimilated
geminates, like underlying ones, are enhanced by additional acoustic attributes, concatenated
geminates are not. Implications of these results for the general issue of geminate behaviour
are discussed, with particular interest on geminate Ambiguity and geminate Inalterability.