Fish Teeth Sr Isotope Stratigraphy and Nd Isotope Variations: New Insights on REY Enrichments in Deep-Sea Sediments in the Pacific

Rare earth elements and yttrium (REY) are widely recognized as strategic materials for advanced technological applications. Deep-sea sediments from the eastern South Pacific and central North Pacific were first reported as potential resources containing significant amounts of REY that are comparable to, or greater than, those of land-based deposits. Despite nearly a decade of research, quantitative abundances and spatial distributions of these deposits remain insufficient. Age controls are generally absent due to the lack of biostratigraphic constraints. Thus, the factors controlling the formation of REY-rich sediments are still controversial. In this study, the REY contents of surface sediments (<2 m depth) in 14 piston cores from the Middle and Western Pacific were investigated. The results show that deep-sea sediments with high REY contents (>1000 μg/g) were mainly concentrated around seamounts (e.g., the Marshall Islands). The REY contents of surface sediments generally decreased with distance from the seamounts. Biostratigraphic and fish teeth debris (apatite) Sr isotopic stratigraphy of one piston cores (P10) from the Middle Pacific indicate that deep-sea sediments with high REY contents were aged from early Oligocene to early Miocene. Since the opening of the Drake Passage during the early Oligocene, the northward-flowing Antarctic Bottom Water (AABW) would have led to an upwelling of nutrients around seamounts with topographic barriers, and at the same time, AABW would delay the rate of sediment burial to try for enough time for REY entering and enriching in the apatite (fish teeth debris). Understanding the spatial distribution of fertile regions for REY-rich sediments provides guidance for searching for other REY resources in the Pacific and in other oceans.

The type section of the Codell Sandstone

We formally assign, describe and interpret a principal reference section for the middle Turonian Codell Sandstone Member of the Carlile Shale near Codell, Kansas. This section, at the informally named Pumpjack Road, provides the thickest surface expression (9 m, ~30 ft) of the unit in Ellis County. The outcrop exposes features that typify the Codell throughout the southern Denver Basin and vicinity. At this reference section, the Codell conformably overlies the Blue Hill Shale Member of the Carlile Shale and is unconformably overlain by the Fort Hays Limestone Member of the Niobrara Formation or locally by a thin (<0.9 m, <3 ft) discontinuous mudstone known as the Antonino facies. The top contact of the Codell is slightly undulatory with possible compaction features or narrow (<30.5 m, <100 ft), low-relief (0.3-0.6 m, 1-2 ft) scours, all of which hint that the Codell is a depositional remnant, even at the type section. At Pumpjack Road, the Codell coarsens upward from a recessive-weathering argillaceous medium-grained siltstone with interbedded mudstone at its base to a more indurated cliff-forming muddy, highly bioturbated, very fine-grained sandstone at its top. The unit contains three informal gradational packages: a lower Codell of medium to coarse siltstone and mudstone, a middle Codell of muddy coarse siltstone, and an upper muddy Codell dominated by well-sorted very fine-grained sandstone. The largest grain fractions, all <120 mm in size, are mostly quartz (40-80%), potassium feldspar (7-12%), and albite (1-2%), with some chert (<15%), zircon, and other constituents such as abraded phosphatic skeletal debris. Rare fossil fish teeth and bones also occur. Detrital and authigenic clays make up 9 to 42% of the Codell at the reference section. Detrital illite and mixed layer illite/smectite are common, along with omnipresent kaolinite as grain coatings or cement. As is typical for the Codell, the sandstone at the type section has been pervasively bioturbated. Most primary structures and bedding are obscured, particularly toward the top of the unit where burrows are larger, deeper and more diverse than at its base. This bioturbation has created a textural inversion in which the larger silt and sand grains are very well sorted but are mixed with mud. Detrital zircons from the upper Codell are unusual in that they are mostly prismatic to acicular, euhedral, colorless, unpitted, and unabraded, and have a near-unimodal age peak centered at ~94 Ma. These characteristics suggest they were reworked mainly from Cenomanian bentonites; their ultimate source was likely from the Cordilleran orogenic belt to the west and northwest.

SPЕCIAL CHILDREN. PERSONAL ORNAMENTS IN CHILDREN’S BURIALS OF MARIUPOL TYPE

The region of the Lower Dnieper was an outstanding landscape phenomenon in prehistoric times. During the Stone Age, this area had great economic and sacral significance. There are more than 20 Mesolithic and Neolithic cemeteries of the so called Mariupol type, located along the Lower Dnieper Rapids. The anthropological analysis demonstrated that the population of Middle Dnieper region belongs to the Proto-European large Europoid race. Periodisation of the Mariupol type cemeteries have two periods: Early Mariupol: 7000—5500 cal BC and Late Mariupol: 5500—4000 cal BC. The burials of the Mariupol type have outstanding grave goods. Raw materials used for used for manufacturing adornments were deer canines, carp fish teeth, stone, pearls and shells. Some burials yielded notched decorated canines. The most outstanding feature of the Mariupol type funerary adornments is the large number of items made from modified boar tusks. Most of them were found in the Mariupol cemetery. These artifacts, which may have marked the membership to a certain group, occurred equally both in adult and children burials. Child burials of the Mariupol type yielded specific funerary adornments. Sometimes they were as rich as those of the adults, but in some cases they were the richest. Personal ornaments, semantically identifying the important parts of a child’s body, were the marker of clan or lineage affiliation, age differentiation or biological stage. Burials with indicating features of a special sacral character are very significant also. The availability of children burials, which have more abundant funerary adornments then the adults, or were the only burials with grave goods in the cemetery need a more thorough study.

Strontium and Oxygen Isotope Analyses Reveal Late Cretaceous Shark Teeth in Iron Age Strata in the Southern Levant

Skeletal remains in archaeological strata are often assumed to be of similar ages. Here we show that combined Sr and O isotope analyses can serve as a powerful tool for assessing fish provenance and even for identifying fossil fish teeth in archaeological contexts. For this purpose, we established a reference Sr and O isotope dataset of extant fish teeth from major water bodies in the Southern Levant. Fossil shark teeth were identified within Iron Age cultural layers dating to 8–9th century BCE in the City of David, Jerusalem, although the reason for their presence remains unclear. Their enameloid 87Sr/86Sr and δ18OPO4 values [0.7075 ± 0.0001 (1 SD, n = 7) and 19.6 ± 0.9‰ (1 SD, n = 6), respectively], are both much lower than values typical for modern marine sharks from the Mediterranean Sea [0.7092 and 22.5–24.6‰ (n = 2), respectively]. The sharks’ 87Sr/86Sr are also lower than those of rain- and groundwater as well as the main soil types in central Israel (≥0.7079). This indicates that these fossil sharks incorporated Sr (87Sr/86Sr ≈ 0.7075) from a marine habitat with values typical for Late Cretaceous seawater. This scenario is in line with the low shark enameloid δ18OPO4 values reflecting tooth formation in the warm tropical seawater of the Tethys Ocean. Age estimates using 87Sr/86Sr stratigraphy place these fossil shark teeth at around 80-million-years-old. This was further supported by their taxonomy and the high dentine apatite crystallinity, low organic carbon, high U and Nd contents, characteristics that are typical for fossil specimens, and different from those of archaeological Gilthead seabream (Sparus aurata) teeth from the same cultural layers and another Chalcolithic site (Gilat). Chalcolithic and Iron Age seabream enameloid has seawater-like 87Sr/86Sr of 0.7091 ± 0.0001 (1 SD, n = 6), as expected for modern marine fish. Fossil shark and archaeological Gilthead seabream teeth both preserve original, distinct enameloid 87Sr/86Sr and δ18OPO4 signatures reflecting their different aquatic habitats. Fifty percent of the analysed Gilthead seabream teeth derive from hypersaline seawater, indicating that these seabreams were exported from the hypersaline Bardawil Lagoon in Sinai (Egypt) to the Southern Levant since the Iron Age period and possibly even earlier.

OXYGEN ISOTOPE PROFILES OF UPPERMOST JURASSIC VERTEBRATE TEETH AND OYSTER SHELLS: A RECORD OF PALEOENVIRONMENTAL CHANGES AND ANIMAL HABITATS

ABSTRACT High resolution oxygen isotopes profiles of well-preserved uppermost Jurassic oyster shells and vertebrate (ichthyosaur and fish) teeth from Central Poland were obtained using a microdrill and an ion microprobe (SHRIMP IIe/MC). Internal variability of δ18O values of oyster shells (-1.7 to 1.3‰ VPDB) collected from the offshore interval of the studied section is greater than that determined previously from bulk oysters. Relatively high δ18O values of the studied oysters may be linked to a slight increase in the salinity of the mid-Polish basin. Low δ18O values of co-occurring ichthyosaur tooth enamel substantiate endothermy of these reptiles. An observed ontogenetic increase in the ichthyosaur enamel δ18O values (from ∼ 19.4 to ∼ 21.6‰ VSMOW) may be a result of long distance migrations although the effect of metabolic factors at rising body mass cannot be completely excluded. It is postulated that δ18O values of the latest portion of the ichthyosaur tooth enamel can be used for the calculation of ancient water oxygen isotope composition and verification of oxygen isotope temperatures. High δ18O values of the enameloid of Caturus lungfishes (23.6 to 26.5‰ VSMOW) collected from an upper part of the studied section, which was deposited in a restricted lagoonal environment after a marine regression, are probably a result of a high evaporation rate. The fishes could have breathed atmospheric air and withstood episodes of water hypoxia. Internal oxygen isotope records of the shells and teeth are promising proxies for studies of the paleoenvironment and activity of animals.