摘要：Some Oligocene fossil benthic assemblages cropping out in the Venetian Prealps near Salcedo (Vicenza) have been investigated on the basis of microfacies analyses, coralline species association, algal structure and growth form. Four facies have been identified: 1) The scleractinian-geniculate coralline facies. This association occurs in a few-metres large bioconstruction (framework) composed of massive small (about 30-40 cm in diameter) coral colonies in life position (Poritidae). Corals are bored by endobionts. Abundant articles of Jania and Amphiroa are associated with the unattached foliose species Neogoniolithon contii (Mastrorilli) Quaranta in the micritic depositis between corals. 2) The scleractinian-nongeniculate coralline facies. Corals appear in life position and are frequently encrusted by dominant Sporolithon pseudokeenani (Mastrorilli), Spongites albanensis (Lemoine) Braga, Bosence & Steneck and Lithoporella melobesioides (Foslie) Foslie. In the micritic deposits also N. contii and an unidentified masthophoroid occur. 3) The nucleated rhodolith facies. Irregularly shaped coralline nodules with fragments of branched corals at the nucleus are dominant over an 8 m thick rudstone with a muddy sand matrix containing a variable percentage of clay. Larger benthic foraminifers (mainly Nummulites fichteli) are common and associated with sparse mollusks, fragments of echinoids and bryozoan colonies. The dominant rhodolith-forming coralline species are Lithothamnion ishigakiense Johnson, S. albanensis, L. melobesioides, Lithoporella minus Johnson, S. pseudokeenani and Mesophyllum sp. Rhodoliths are commonly multispecific, contain micritefilled voids and have a laminar-concentric to boxwork internal structure. Unattached foliose thalli of ?Lithothamnion moretii Lemoine Lithothamnion roveretoi Airoldi and N. contii are common in the matrix
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