This paper presents an automatic approach for the detection of the prosodic structures of speech utterances. The algorithm relies on a hierarchical representation of the prosodic organization of the speech utterances. The approach is applied on a corpus of radio French broadcast news and also on radio and TV shows which are more spontaneous speech data. The algorithm detects prosodic boundaries whether they are followed or not by pause. The detection of the prosodic boundaries and of the prosodic structures is based on an approach that integrates little linguistic knowledge and mainly uses the amplitude of the F0 slopes and the inversion of the slopes as described in [1], as well as phone durations. The automatic prosodic segmentation results are then compared to a manual prosodic segmentation made by an expert phonetician. Finally, the results obtained by this automatic approach provide an insight into the most frequently used prosodic structures in the broadcasting speech style as well as in a more spontaneous speech style.