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- Middle-Upper Jurassic palynology of the Sagres region and the Carrapateira outlier: southern PortugalPublication . Borges, Marisa; Fernandes, Paulo; Pereira, Zélia; Riding, JimThe palynology of the Middle-Upper Jurassic fill of the Sagres region (Algarve Basin) and the Carrapateira outlier, southern Portugal was investigated. Samples were collected from Mareta beach, Cilheta beach and the Carrapateira outlier. Dinoflagellate cysts are confined to the Upper Bajocian to Upper Callovian sedimentary rocks exposed at Mareta and Cilheta beaches and the Lower Kimmeridgian strata of the Carrapateira outlier. The palynostratigraphical study of the Jurassic successions has yielded new biostratigraphical data based on dinoflagellate cysts and miospores. The results confirm, and in some cases refine, the existing macrofaunal age determinations of these successions.
- Jurassic palynostratigraphy of the Algarve Basin and the Carrapateira Outlier, Southern PortugalPublication . Borges, Marisa; Riding, James B.; Fernandes, Paulo; Pereira, ZéliaThe Mesozoic Algarve Basin (AB) corresponds to the southernmost geological province of mainland Portugal. The Carrapateira Outlier (CO) is a small outcrop of Mesozoic rocks located 20 km north of the AB. In this study we investigated the palynology of the Jurassic (Upper Bajocian to Lower Kimmeridgian) of the AB and CO.
- The Middle Jurassic palynology of the Sagres region, southern Portugal.Publication . Borges, Marisa; Fernandes, Paulo; Pereira, Zélia; Riding, JimThe Algarve Basin corresponds to the southernmost geological province of mainland Portugal. It has an E-W strike and is represented onshore from Cap São Vicente to the Guadiana River on the Portuguese-Spanish border. More than 3000 m of essentially marine sediments accumulated during Mesozoic-Cenozoic times in the Algarve Basin.
- The Jurassic (Pliensbachian to Kimmeridgian) palynology of the Algarve Basin and the Carrapateira outlier, southern PortugalPublication . Borges, Marisa; Riding, James B.; Fernandes, Paulo; Pereira, ZéliaThe palynology of the Jurassic (Upper Pliensbachian to Lower Kimmeridgian) fill of the Algarve Basin and the Carrapateira outlier, southern Portugal was investigated. Samples were collected from Armação Nova Bay, Mareta Beach, Cilheta Beach and the Carrapateira outlier. At Armação Nova Bay the Upper Pliensbachian–Lower Toarcian succession proved barren, or yielded sparse, non age-diagnostic palynomorphs. Dinoflagellate cysts are confined to the Upper Bajocian to Upper Callovian sedimentary rocks exposed at Mareta and Cilheta beaches and the Lower Kimmeridgian strata of the Carrapateira outlier. At Mareta Beach, the Upper Bajocian, Bathonian and Callovian produced relatively low to moderate diversity dinoflagellate cyst assemblages. Several key bioevents confirm the Bathonian and Callovian ages of the succession; no age-significant Late Bajocian bioevents were noted. The Upper Callovian of Cilheta Beach yielded moderately diverse dinoflagellate cyst associations dominated by Ctenidodinium spp. Key Late Callovian bioevents confirm the age of this succession. Many familiar marker forms known from northwest Europe were not encountered. No typically Arctic forms were recovered throughout the Upper Bajocian to Callovian of this part of the Algarve Basin. It is clear that there was no significant Late Bajocian to Late Callovian dinoflagellate cyst provincialism within southern and northern Europe and adjacent regions. The Carrapateira outlier yielded a moderately diverse Early Kimmeridgian dinoflagellate cyst flora. The Early Kimmeridgian age assessment based on corals and foraminifera is confirmed. Amphorula and Histiophora are present; these are typical of the Late Jurassic of the Tethyan Realm, and their presence is consistent with Late Jurassic provincialism within Europe. The relatively low diversity nature of these Late Bajocian to Early Kimmeridgian dinoflagellate cyst floras is probably mainly due to the relatively deep water, partially enclosed depositional setting. The partially enclosed nature of this part of the Algarve Basin and the Carrapateira outlier seems to have prevented the free migration of dinoflagellates between southern Portugal and elsewhere in Europe.