The fan-shaped Balearic rise, southeast of the islands of Mallorca and Menorca, lies at the base of the Emile Baudot escarpment at a depth of 1,600-2,600 m. A sparker, 3.5 Khz profiler, and coring survey reveals that the rise, unlike most deep-sea fans, is almost entirely tectonic in origin. It is a post-Miocene, block-faulted terrane with a thin sediment cover. A large valley, heading between Mallorca and Menorca, follows

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in its upper sector a major, pre-Pliocene, NNW-SSE-trending fault. Its floor is 3-4 km wide at the head and 25 km wide near the base of the rise; at present, the upper valley serves as a funnel for sediment moving downslope. The lower valley, filled by thick (about 700 m) sediment, indicates that the valley served as a sediment trap during most of Quaternary time.

The steep (to 15°), straight, northeast-southwest-trending Emile Baudot escarpment is a young, possibly still active, fault plane to which the main foundering of the rise is related. The down-dropping is so recent that pre-Pliocene bedrock on the rise remains partly exposed. The unconsolidated material on the rise is Quaternary sand and mud, turbidites, and hemipelagites, as well as older sediment reworked from the upper Balearic platform Some of these sediments presumably originated at the proto-Ebro River system on the northwest and were deposited in deltaic and nearshore environments in an area which now lies between Mallorca and Menorca. The Ebro sediment source was cut off as a result of the separation of the Balearic block from the Iberian Peninsula before the deposition of the Miocene evaporites.

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