Fossil plants found at the north-east tip of Nelson Island (Rip Point), South Shetland Islands, during the expeditions of Brazilian Antarctic Program, give an additional support to a warm temperate and wet conditions of the climate during Late Cretaceous (Campanian?) in the fore-arc environments of northern Antarctic Peninsula (Dutra et alii, 1996 e Dutra, 1997a). The impressions of leaves were found in a near sea 20 m exposure composed by lower tuffaceous breccia, with chaotically arranged andesitic and basaltic clasts and intercalated tuffs with coalified pieces of wood, followed by two finning upward succession of conglomerate, lenticular fine to coarse lapilistones and laminated dark grey, green and brown pelitic tuffaceous beds. The sequence is very similar to other ones found at Fildes Peninsula, south-western part of the nearby King George Island (Dutra et alii, 1996) where they are covered by lavas with K-Ar ages from 71 to 77 My (Shen, 1994). The sedimentological characteristics of the fossiliferous beds pointed out to a braided river depositional context with interdistributary lakes in a non-confined regime, formed in an erosional phase during syneruption conditions (sensu Smith, 1991).

The layers exhibit a high level of alteration and disaggregation, which makes difficult to obtain complete samples of the rare macrofossils and only permit to approximate the taxonomic affinity of the leaves. Many of them are covered by a white film (chlorite?) very similar to other cretaceous occurrences in these islands, consequence of the breakdown of