REE Signatures in Vertebrate Fossils from Sewell, NJ: Implications for Location of the K-T Boundary

Staron, Richard M.; Grandstaff, Barbara S.; Gallagher, William B.; Grandstaff, David E.

doi:10.2307/3515603

Cited by 7 publications

(12 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For example, in her discussion of fluvially influenced bone accumulations, Behrensmeyer (1982) suggested that bones derived from various taphonomic pathways might eventually be distinguished based on differences in chemical characteristics. Since that time, researchers have developed methods using lanthanide, or rare earth elements (REE), in fossil bones to determine their stratigraphic associations, provenance, taphonomic history, paleoenvironment, and degree of reworking (Wright et al, 1987;Trueman and Benton, 1997;Reynard et al, 1999;Trueman, 1999;Staron et al, 2001;Trueman et al, 2003Trueman et al, , 2005Trueman et al, , 2006Metzger et al, 2004;Patrick et al, 2004;Martin et al, 2005). Rare earth element analyses of fossil bones, coupled with traditional methods of taphonomic analysis, allow researchers to more fully distinguish bones affected by various taphonomic processes and from multiple stratigraphic sources.…”

Section: Introductionmentioning

confidence: 99%

Rare Earth Element Geochemistry and Taphonomy of the Early Cretaceous Crystal Geyser Dinosaur Quarry, East-Central Utah

Suarez

Terry

et al. 2007

PALAIOS

View full text Add to dashboard Cite

The Crystal Geyser Dinosaur Quarry contains a large monospecific accumulation of bones from a basal therizinosaur, Falcarius utahensis. The quarry is located approximately 16 km south of Green River, Utah, at the base of the early Cretaceous (Barremian) Yellow Cat Member of the Cedar Mountain Formation. Fossil bones in the quarry occur in three units that have distinct taphonomic, lithologic, and geochemical characteristics. Rare earth element compositions of fossils suggest that bones from each unit were drawn from different reservoirs or sources having distinctly different compositions, and fossils were not reworked between units. Compositions of bones differ greatly within Units 1 and 2, even within the same 1-m 2 quarry grid. These chemical differences and taphonomic characteristics, such as current orientation, hydraulic sorting, and occasional extensive abrasion, suggest that bones from these two units are allochthonous and were fossilized at other localities, possibly over an area of several kilometers, and were then eroded, transported, and concentrated in a spring-influenced fluvial environment. Bones in Unit 3 have very similar rare earth element signatures, suggesting that they were probably fossilized in situ at a separate time from bones in Units 1 and 2. At least two mass mortality events were responsible for the monospecific assemblage of bones at the quarry. Because bones may have been concentrated from a wide area, causes of mass mortality must have been regionally extensive, possibly owing to seasonal drought, sudden changes in weather, or disease.

show abstract

Section: Introductionmentioning

confidence: 99%

Rare Earth Element Geochemistry and Taphonomy of the Early Cretaceous Crystal Geyser Dinosaur Quarry, East-Central Utah

Suarez

Terry

et al. 2007

PALAIOS

View full text Add to dashboard Cite

show abstract

“…Direct dating of skeletal material from Australian late Pleistocene contexts has been problematic, and few studies have produced unequivocal results (7,8). The analysis of rare earth element (REE) contents in bone has emerged recently as a valuable test for stratigraphic associations (9)(10)(11)(12)(13). In buried bone, REEs are adsorbed rapidly from pore waters onto bone crystal surfaces and then locked in the bone crystal lattice during recrystallization (9).…”

mentioning

confidence: 99%

“…Therefore, bones in successive depositional units frequently inherit distinct REE patterns. Subsequent postdepositional mixing of fossils from different primary depositional localities may be detected by comparing REE signals within and between assemblages of bones (9)(10)(11)13). Here, we apply REE analyses to a faunal assemblage from the late Pleistocene archeological site of Cuddie Springs, which is an ephemeral lake in southeastern Australia (see Fig.…”

mentioning

confidence: 99%

Prolonged coexistence of humans and megafauna in Pleistocene Australia

Trueman

Field

Dortch

et al. 2005

Proc. Natl. Acad. Sci. U.S.A.

120

View full text Add to dashboard Cite

Recent claims for continent wide disappearance of megafauna at 46.5 thousand calendar years ago (ka) in Australia have been used to support a ''blitzkrieg'' model, which explains extinctions as the result of rapid overkill by human colonizers. A number of key sites with megafauna remains that significantly postdate 46.5 ka have been excluded from consideration because of questions regarding their stratigraphic integrity. Of these sites, Cuddie Springs is the only locality in Australia where megafauna and cultural remains are found together in sequential stratigraphic horizons, dated from 36 -30 ka. Verifying the stratigraphic associations found here would effectively refute the rapid-overkill model and necessitate reconsideration of the regional impacts of global climatic change on megafauna and humans in the lead up to the last glacial maximum. Here, we present geochemical evidence that demonstrates the coexistence of humans and now-extinct megafaunal species on the Australian continent for a minimum of 15 ka.archeology ͉ extinction ͉ geochemistry ͉ rare earth element ͉ climate change L ate Quaternary extinctions of megafauna have been documented on all continents except Antarctica, and in North America and Australia, these extinctions have broadly coincided with human colonization (1, 2). In Australia, conservative estimates place human arrival on this continent at Ϸ43-45 thousand calendar years ago (ka), although some researchers argue for colonization up to 60 ka (3). Intense debate surrounds the timing and causes of megafaunal extinctions in Australia, especially in resolving the relative roles of humans and climate (1-6). The following three explanatory hypotheses ( Fig. 1) dominate the discussion.1. Human overkill, or ''blitzkrieg,'' in which megafauna went extinct within 1,000 years of human arrival, with megafauna disappearing by 46.5 ka. 2. Habitat modification by humans through firing the landscape and associated hunting, with extinctions complete by 46.5 ka. 3. A paleoecological explanation in which climate change was the driving force in megafauna demise as factors such as increasing aridity, habitat reconfiguration, competitive exclusion, and possibly the added pressures of a new predator combined to suppress and ultimately drive to extinction a suite of Australian fauna.Developing extinction chronologies has generally relied on the dating of sediments associated with megafaunal remains (2). Direct dating of skeletal material from Australian late Pleistocene contexts has been problematic, and few studies have produced unequivocal results (7,8). The analysis of rare earth element (REE) contents in bone has emerged recently as a valuable test for stratigraphic associations (9-13). In buried bone, REEs are adsorbed rapidly from pore waters onto bone crystal surfaces and then locked in the bone crystal lattice during recrystallization (9). The relative abundances of REEs sequestered into bone are controlled by the immediate pore water chemistry. Therefore, bones in successive depositional units frequen...

show abstract

“…Sample preparation techniques follow those by Staron et al (2001). Large intact bone specimens were sampled by drilling using a Dremel variablespeed electric drill.…”

Section: Methodsmentioning

confidence: 99%

Lithostratigraphy, Tephrochronology, and Rare Earth Element Geochemistry of Fossils at the Classical Pleistocene Fossil Lake Area, South Central Oregon

Martin

Patrick

Kihm

et al. 2005

The Journal of Geology

View full text Add to dashboard Cite

One of the most famous fossiliferous Pleistocene sites in the Pacific Northwest is Fossil Lake, Oregon. Until recently, fossil collections from the area were not stratigraphically controlled, owing to the lack of a detailed stratigraphic and chronologic framework. Our field studies reveal at least nine exposed thin rhythmic fining-upward depositional packages, most separated by disconformities. Analysis of interbedded tephras reveals that the Rye Patch Dam (∼646 ka), Dibekulewe (∼610 ka), Tulelake T64 (∼95 ka), Marble Bluff (47 ka), and Trego Hot Springs (23.2 ka) tephra layers are present in the section, indicating deposition from more than ∼646 ka to less than 23 ka, which includes both the late Irvingtonian and Rancholabrean North American land mammal ages, a much longer time span than previously believed. Bones analyzed from eight of the defined units have distinctly different rare earth element (REE) signatures. Fossils obtain REE during early diagenesis, and signatures are probably closely related to lake water compositions. REE signatures in fossils from lower packages suggest uptake from neutral pH waters. In contrast, REE signatures become increasingly heavy REE-enriched up-section, with positive Ce anomalies in the upper units. REE signatures in fossils from the upper units are very similar to waters from modern alkaline lakes, such as Lake Abert, Oregon, suggesting diagenetic uptake in increasingly alkaline and saline waters. These REE changes suggest increasing aridity up-section, a contention reinforced by the habitat preferences of the terrestrial vertebrates preserved.

show abstract

REE Signatures in Vertebrate Fossils from Sewell, NJ: Implications for Location of the K-T Boundary

Cited by 7 publications

References 0 publications

Rare Earth Element Geochemistry and Taphonomy of the Early Cretaceous Crystal Geyser Dinosaur Quarry, East-Central Utah

Rare Earth Element Geochemistry and Taphonomy of the Early Cretaceous Crystal Geyser Dinosaur Quarry, East-Central Utah

Prolonged coexistence of humans and megafauna in Pleistocene Australia

Lithostratigraphy, Tephrochronology, and Rare Earth Element Geochemistry of Fossils at the Classical Pleistocene Fossil Lake Area, South Central Oregon

Contact Info

Product

Resources

About