Lisbon Formation Research Articles

Taxonomy and biostratigraphy of the elasmobranchs and bony fishes (Chondrichthyes and Osteichthyes) of the lower-to-middle Eocene (Ypresian to Bartonian) Claiborne Group in Alabama, USA, including an analysis of otoliths

The Tallahatta Formation, Lisbon Formation, and Gosport Sand are the three lithostratigraphic units that make up the lower-to-middle Eocene Claiborne Group. In Alabama, these marine units are among the most fossiliferous in the state and a long history of scattered reports have attempted to document their fossil diversity. In this study, we examined 20931 elasmobranch and bony fish elements, including otoliths, derived from Claiborne Group units in Alabama and identified 115 unequivocal taxa. Among the taxa identified, one new species is described, Carcharhinus mancinae sp. nov., and Pseudabdounia gen. nov. is a new genus erected to include two species formerly placed within Abdounia Capatta, 1980. New taxonomic combinations proposed include Pseudabdounia claibornensis (White, 1956) gen. et comb. nov., Pseudabdounia recticona (Winkler, 1874) gen. et comb. nov., Physogaleus alabamensis (Leriche, 1942) comb. nov., and Eutrichiurides plicidens (Arambourg, 1952) comb. nov. We also report the first North American paleobiogeographic occurrences of Aturobatis aff. A. aquensis Adnet, 2006, Brachycarcharias atlasi (Arambourg, 1952), Eutrichiurides plicidens comb. nov., Galeorhinus louisi Adnet & Cappetta, 2008, Ginglymostoma maroccanum Noubhani & Cappetta, 1997, Gymnosarda sp., Mennerotodus sp., Rhizoprionodon ganntourensis (Arambourg, 1952), Stenoscyllium aff. S. priemi Noubhani & Cappetta, 1997, Trichiurus oshosunensis White, 1926, and the first North American occurrence for a fossil member of the Balistidae Risso, 1810. Our sample also included 26 taxa that represented first paleobiogeographic occurrences for Alabama, including Abdounia beaugei (Arambourg, 1935), Albula eppsi White, 1931, Ariosoma nonsector Nolf & Stringer, 2003, Anisotremus? sp., Anomotodon sp., Brachycarcharias twiggsensis (Case, 1981), Burnhamia daviesi (Woodward, 1889), Eoplinthicus yazooensis Capetta & Stringer, 2002, Galeorhinus ypresiensis (Casier, 1946), Gnathophis meridies (Frizzell & Lamber, 1962), Haemulon? obliquus (Müller, 1999), Hypolophodon sylvestris (White, 1931), Malacanthus? sulcatus (Koken, 1888), Meridiania cf. M. convexa Case, 1994, Palaeocybium proosti (Storms, 1897), Paraconger sector (Koken, 1888), Paralbula aff. P. marylandica Blake, 1940, Phyllodus toliapicus Agassiz, 1844, Propristis schweinfurthi Dames, 1883, Pycnodus sp., Pythonichthys colei (Müller, 1999), Scomberomorus stormsi (Leriche, 1905), Signata stenzeli Frizzell & Dante, 1965, and Signata nicoli Frizzell & Dante, 1965, and the first Paleogene occurrences in Alabama of a member of the Gobiidae Cuvier, 1816. A biostratigraphic analysis of our sample showed stratigraphic range extensions for several taxa, including the first Bartonian occurrences of Eoplinthicus yazooensis, Jacquhermania duponti (Winkler, 1876), Meridiania cf. M. convexa, Phyllodus toliapicus, and “Rhinobatos” bruxelliensis (Jaekel, 1894), range extensions into the late Ypresian and Bartonian for Tethylamna dunni Cappetta & Case, 2016 and Scoliodon conecuhensis Cappetta & Case, 2016, the first late Ypresian records of Galeorhinus louisi, the first Lutetian occurrence of Gymnosarda Gill, 1862, and a range extension for Fisherichthys aff. F. folmeri Weems, 1999 into the middle Bartonian. Larger biostratigraphic and evolutionary trends are also documented, such as the acquisition of serrations in Otodus spp., possible population increases for the Rhinopterinae Jordan & Evermann, 1896 and Carcharhiniformes Compagno, 1973 in the Bartonian, and the apparent diversification of the Tetraodontiformes Berg, 1940 during the same stage. This study helps better our understanding of early-to-middle Eocene elasmobranch and bony fish diversity, paleobiogeography, and biostratigraphy in the Gulf Coastal Plain of North America.

A Selachian Fauna from the Middle Eocene (Lutetian, Lisbon Formation) of Andalusia, Covington County, Alabama, USA

A Selachian Fauna from the Middle Eocene (Lutetian, Lisbon Formation) of Andalusia, Covington County, Alabama, USA

New data on the palaeontology and sedimentology of the Lower Jurassic Lisbon Formation (Karoo Supergroup), Ellisras Basin, South Africa

Published records on the palaeontology of the Lower Jurassic Lisbon Formation in the Ellisras Basin (a South African continuation of the Botswana Kalahari Karoo Basin) are virtually non-existent. Here we review the geology of this extremely poorly exposed unit, and describe a newly discovered ichnofossil and fossil vertebrate association, consisting of constructed structures resembling termitaria as well as of basal sauropodomorph remains. Our paleontological and sedimentological analyses permit a direct bioand lithostratigraphic correlation of the Lisbon Formation at farm Lisbon with the upper part of the Elliot Formation in the main Karoo Basin as well as other Lower Jurassic continental red bed successions throughout southern Africa. We tentatively suggest that the formation (especially its upper part) was deposited in a dryland setting with well-drained soils that at least episodically supported some flora and a fauna probably dominated by basal sauropodomorphs.

ABSTRACT: Subsurface Sequence Stratigraphic Analysis of the Eocene-Lower Oligocene of Alabama

Abstract South Alabama contains world-class outcrops of Eocene and Oligocene strata that have been the object of intense scrutiny over the past 50 years. Despite such thorough examination, these outcrops have failed to assuage controversy as to the physical nature of the Eocene/Oligocene (E/O) boundary in this region. Some workers have made this faunal boundary coincident with a sequence boundary, while others place it within a stratigraphically condensed section during a relative sea level highstand. This problem is exacerbated by the fact that because outcrops in Alabama are limited in areal extent, large-scale stratal patterns such as onlap and downlap have not been used to place constraints on this matter. A grid of wireline logs (SP and resistivity) has been assembled and digitized in the area of interest to examine the nature of the E/O boundary on a seismic scale. The log data are calibrated to lithology and biostratigraphy using two stratigraphic test cores. In these cores the Eocene/Oligocene boundary, defined using multiple biostratigraphic events, occurs in a relatively fine-grained interval bounded by unconformities. These unconformities are interpreted as sequence boundaries amalgamated with transgressive surfaces of erosion. To address the physical nature of the E/O boundary on a regional scale, transgressive-regressive (T-R) cycles reflected in the wireline logs are currently being analyzed and correlated. Mapping T-R cycles into the subsurface of Alabama provides information that was unavailable to earlier field-based workers. In addition, such mapping may clear up other areas of contention, such as the number of cycles in the middle Eocene Lisbon Formation. End_of_Record - Last_Page 711-------

The Eocene larger foraminifer Lepidocyclina ariana Cole and Ponton, from the so-called Polylepidina gardnerae horizon at Little Stave Creek, Alabama

Recent sampling for larger foraminifers in the so-called Polylepidina gardnerae horizon in the middle Eocene Lisbon Formation of the Little Stave Creek section, southwest Alabama, did not produce any examples of the lepidocyclinid foraminifer Polylepidina gardnerae Cole, but several specimens of the stratigraphically younger species, Lepidocyclina ariana Cole and Ponton, were recovered. Although the P. gardnerae horizon is named on nearly all figures of this important Gulf Coast section published since 1944, preliminary research has also failed to turn up a published basis for the identification of P. gardnerae at this locality. As L. ariana and P. gardnerae are not normally found together, it is the writer's opinion that true P. gardnerae probably has not been collected from any part of the Lisbon Formation at Little Stave Creek. If it does occur, it should be found at a lower horizon than that indicated in the literature.

Pseudorhombodinium lisbonensegen. et sp. nov., a new dinoflagellate fossil from the Lisbon formation (middle Eocene), Little Stave Creek, Alabama

Abstract Specimens of Pseudorhombodinium lisbonense gen. et sp. nov., the type species of the new fossil dinoflagellate genus Pseudorhombodinium gen. nov., were recovered from an outcrop of the lower part of the Lisbon Formation (middle Eocene) in Little Stave Creek, Clarke County, Alabama. The sample containing P. lisbonense gen. et sp. nov. is a calcareous glauconitic sand bed located approximately 104 ft above the Jackson Fault, the reference datum for the base of the Paleogene section exposed in Little Stave Creek. Whether Pseudorhombodinium gen. nov. is a dinoflagellate cyst (dinocyst) or the remains of a thecate, motile dinoflagellate is uncertain. However, for convenience it will be treated as a dinocyst in this paper. Pseudorhombodinium is established to accommodate organic‐walled, subrhombic to subpentagonal shaped, circumcavate dinocysts with a hexa paratabulation style and 2a intercalary archeopyle, Type Ia/Ia. The periarcheopyle is iso‐deltaform, the endoarcheopyle is eury‐deltaform, and the o...

Evolution of the Foraminiferal Genus Lepidocyclina in the Middle Eocene and Its Implication for Gulf Coast Stratigraphy: ABSTRACT

ABSTRACT Based on data from some 40 samples, the first appearance of the Lepidocyclina ariana larger foraminiferal species group occurs at a horizon within the transgressive depositional system of Baum and Vail's TE3.1 sequence, as recently defined by Baum and others in the Bay Minette corehole, Alabama. The last occurrence of the genus Polylepidina Vaughan is observed in the same system in this core. These events also occur within the upper part of the Lisbon Formation as defined in the classical surface section at Little Stave Creek, Alabama, and at other localities in the Gulf Coast, corresponding to a biostratigraphic horizon near that of the boundary between the NP16 and NP17 calcareous nannofossil zones, of middle Eocene, Bartonian age. We illustrate the implication for dating and correlation at horizons near the middle Eocene - late Eocene boundary by the presentation of a correlation of part of the Bay Minette corehole with the section at Little Stave Creek, based on larger foraminiferal and calcareous nannofossil data. We discuss this correlation in relation to other selected localities in the Gulf Coast.

Cirriped assemblage zones of the eocene claibornian and jacksonian stages, southeastern Atlantic and Gulf Coastal Plains

Two Eocene cirriped assemblage zones are recognized in the Gulf Coastal Plain of Alabama and Mississippi. The Arcoscalpellum subquadratum Zone is characterized by A. subquadratum (Meyer and Aldrich), Aporolepas americana (Withers), Euscalpellum eocenense (Meyer), and Solidobalanus antiquus (Meyer), and ranges through the upper Claibornian Stage. The Arcoscalpellum jacksonense Zone is characterized by A. jacksonense Withers, A. choctawensis Weisbord, Aporolepas howei Cheetham, and Solidobalanus sp. aff. S. antiquus (Meyer), and ranges through the Jacksonian Stage. Representative species of one or both of these cirriped zones are found also in Texas, Georgia, South Carolina, and North Carolina, and afford an additional means for correlating Claibornian and Jacksonian marine units between the Atlantic and Gulf Coastal Plains. The Arcoscalpellum subquadratum Zone is represented in the Cook Mountain Formation of Texas and Mississippi, the upper Lisbon Formation and overlying Gosport Sand of Alabama, the McBean Formation of Georgia, and the Cubitostrea sellaeformis beds of the restricted Santee Limestone of South Carolina. The A. jacksonense Zone is represented in the Moodys Branch Formation of Mississippi and Alabama, the Cocoa Sand of Alabama, the Pachuta Marl of either Mississippi or Alabama, the Shubuta Clay equivalents in Alabama, the Clinchfield Sand and Dry Branch Formation of Georgia, the Cross Formation of South Carolina, and the biosparrudite and biomicrudite members of the Castle Hayne Limestone in North Carolina. Some cirriped species found in these zones in the southeastern Atlantic Coastal Plain are not represented in the Gulf Coastal Plain. Solidobalanus n. sp. 1, a species unrelated to the S. antiquus group, occurs in the McBean Formation of Georgia ( Arcoscalpellum subquadratum Zone). Kathpalmeria georgiana Ross is found in the Griffins Landing Member of the Dry Branch Formation of Georgia and has tentatively been identified from the Inglis Formation of northern Florida ( Arcoscalpellum jacksonense Zone). Euscalpellum carolinensis Zullo and Baum and Solidobalanus n. sp. 2 (related to Solidobalanus n. sp. 1) are found in the Cross Formation of South Carolina and the Castle Hayne Limestone of North Carolina ( Arcoscalpellum jacksonense Zone). Recognition of the A. jacksonense Zone in the Cross Formation and the Castle Hayne Limestone supports recent conclusions based on calcareous nannofossil zonation and radiometric determinations that these units are Jacksonian rather than Claibornian in age.

RbSr glauconite ages, Sabinian, Claibornian and Jacksonian units, southeastern Atlantic Coastal Plain, U.S.A

Hand-picked, disordered to ordered authigenic glauconite from the Nanjemoy Formation (Virginia), the Santee Limestone (restricted) and Cross Formation (South Carolina), and the Castle Hayne Limestone (North Carolina) yield RbSr isochron ages ( λ 87Rb = 1.42 × 10 −11 yr −1) for Eocene units in the southeastern Atlantic Coastal Plain. The units, zonal assignment of their contained nannofossil floras and radiometric age, are: 3 Unit Nannofossil zone Age (m.y.) Castle Hayne Limestone NP 19–20 34.9 ± 1.1 Cross Formation NP 18, NP 19, NP 20 34.1 ± 1.5 Santee Limestone (upper part) NP 16–17 36.7 ± 0.6 Nanjemoy Formation NP 13 46.7 ± 3.0 These ages, and their nannofossil assemblages, provide means of correlating southeastern Atlantic Coastal Plain units with Gulf Coastal Plain and European stratoypes. Correlation to Gulf Coast stratotypes, based on nannofossil zones, indicates that the Nanjemoy Formation (in part) is equivalent to the Hatchetigbee Formation; the upper part of the Santee Limestone (restricted) is equivalent to the upper Lisbon Formation, the Gosport Sand, and the Moodys Branch Formation (upper Claibornian-lower Jacksonian); and the Cross Formation and the Castle Hayne Limestone are equivalent to the Yazoo Group (Jacksonian). Previously reported KAr glauconite ages for the Gulf Coast units are different from the RbSr ages determined in this study. As the RbSr age determinations show internal consistency when compared to their contained nannofossil zones, whereas the KAr ages do not, it is suggested that the previously reported KAr ages for the Gulf Coast Claibornian and Jacksonian are in error. Correlation of the southeastern Atlantic Coastal Plain units to European stratoypes based on nannofossil zones indicates that the Nanjemoy Formation (in part) is equivalent to the type Lutetian; the upper part of the Santee Limestone (restricted) is equivalent to the Upper Bracklesham and Barton Beds; and the Cross Formation and Castle Hayne Limestone are equivalent to the Lower and Middle Headon Beds. Previously determined KAr and RbSr radiometric ages for the type Lutetian, the Bracklesham and Barton Beds are identical to the ages determined in this study. As a result, it is suggested that Rb-Sr glauconite isochron ages can be used for regional and inter-regional correlation and that the Eocene/Oligocene boundary is younger than 34 m.y.

Provincialism among Mid-Eocene Calcareous Nannofossils

Pentaliths, one new genus, six new species, good stratigraphic markers and indicators of hemipelagic environment, Lisbon Formation, Alabama