Minateda rock shelters (Albacete) and post-palaeolithic art of the Mediterranean Basin in Spain: pigments,surfaces and patinas

The inorganic and organic fractions of two microsamples of prehistoric paint from the same site, the Minateda rock shelters, are analysed here for the first time. The two samples correspond to two rock shelters of different styles (Levantine and schematic) – Abrigo Grande de Minateda (The Great Rock Shelter of Minateda) and Abrigo del Barranco de la Mortaja (Del Barranco de la Mortaja Rock Shelter). Since its discovery, historiographical tradition has emphasised the Abrigo Grande de Minateda, with its magnificence and complexity, as emblematic of the origin and evolution of rock art in the Mediterranean Basin of the Iberian Peninsula (a UNESCO World Heritage Site). Four complementary techniques –Microphotography, Scanning Electron Microscopy-Energy Dispersive X-Ray Spectroscopy (SEM-EDX), Raman Spectroscopy and Gas Chromatography–Mass Spectroscopy (GC–MS)– were combined to identify and characterise the physicochemical properties of the paint and of the surface. We present an interpretation of the results that leads us to define complex taphonomic alterations beyond the usual distinction of layers that include the surface, pigments and patinas.     

Dating North America's oldest petroglyphs,Winnemucca Lake subbasin,Nevada

On the west side of the Winnemucca Lake subbasin, Nevada, distinctive deeply carved meter-scale petroglyphs are closely spaced, forming panels on boulder-sized surfaces of a partially collapsed tufa mound. The large, complex motifs at this side are formed by deeply carved lines and cupules. A carbonate crust deposited between 10 200 and 9800 calibrated years B.P. (ka) coats petroglyphs at the base of the mound between elevations of 1202 and 1206 m. Petroglyphs above the carbonate crust are carved into a branching form of carbonate that dates to 14.8 ka. Radiocarbon dates on a multiple-layered algal tufa on the east side of the basin, which formed at an elevation of 1205 m, as well as a sediment-core-based total inorganic carbon record for the period 17.0–9.5 ka indicate that water level in the Winnemucca Lake subbasin was constrained by spill over the Emerson Pass Sill (1207 m) for most of the time between 12.9 ± 0.3 and ≥9.2 ka. These and other data indicate that the lake in the Winnemucca Lake subbasin fell beneath its spill point between 14.8 and 13.2 ka and also between 11.3 and 10.5 ka (or between 11.5 and 11.1 ka), exposing the base of the collapsed tufa mound to petroglyph carving. The tufa-based ¹⁴C record supports decreased lake levels between 14.8–13.2 ka and 11.3–10.5 ka. Native American artifacts found in the Lahontan Basin date to the latter time interval. This does not rule out the possibility that petroglyph carving occurred between 14.8 and 13.2 ka when Pyramid Lake was relatively shallow and Winnemucca Lake had desiccated.     

Paleoindian technological provisioning strategies in the northwestern Great Basin

Great Basin populations during the Pleistocene–Holocene Transition (PHT) are often characterized as being mobile and focused on wetlands; however, the factors that influenced where Paleoindians selected residential campsites are poorly understood. Using predictions derived from optimal foraging-based patch choice models and GIS reconstructions of the PHT landscape, some researchers have argued that occupations in smaller wetlands should have been shorter than occupations in larger wetlands but such arguments have rarely been evaluated using empirical data. The PHT lithic record provides an opportunity to evaluate the relationship between wetland size and occupation span by applying Kuhn's (1995) concept of technological provisioning. Kuhn expects more mobile populations to provision individuals and more sedentary populations to provision places and suggests that: (1) a strategy of provisioning individuals should be reflected by a high proportion of more extensively used artifacts made on non-local raw materials; and (2) a strategy of provisioning places should be reflected by a high proportion of less extensively used artifacts made on local raw materials. We apply the technological provisioning concept to lithic assemblages from two of the Parman localities, extensive PHT sites in the northwestern Great Basin, and compare local and nonlocal artifacts to determine if Paleoindians shifted from provisioning individuals while moving to/from the sites to provisioning the place while occupying them. There is no relationship between artifact transport distance and artifact use intensity. We interpret these findings as evidence that Paleoindians did not alter their provisioning strategies while occupying the Parman localities, likely because occupations were brief within a small wetland poorly-suited to support groups for long periods.     

Oligocene-Miocene palynomorphs from subsurface sediments,West Bengal,India

Palynological studies of Cenozoic sediments from borehole PGD-1A in the easternmost extension of the Damodar Basin, West Bengal, India, provide important new palynological data from this basin, where previous data are rare. The palynoassemblage includes Striatriletes, Crassoretitriletes, Bacutriporites, Cauveripollis, Cheilanthoidspora, Palaeomalvaceaepollis, Tricollareporites, Pinuspollenites and Tsugaepollenites which suggest a late Oligocene - early Miocene age. Dinocyst genera such as Selenopemphix, Tuberculodinium, Hystrichokoipoma and Thalasiphora, recorded from the borehole, also support this age assignment. The assemblage indicates a tropical to subtropical humid climate with high rainfall. Deposition of the studied strata took place in a delta under shallow marine influence; this is the first evidence that a marine transgression extended into the Damodar Basin and that mangrove forest developed in the area.     

Non-marine ?Late Silurian-Early Devonian trace fossils,Darling Basin,western New South Wales

An ichnofauna consisting of four types of trackways and five types of traces, largely made by arthropods, was discovered in the ?Late Silurian-Early Devonian Mt Daubeny Formation in western New South Wales. The trackways include forms of Diplichnites gouldi, Merostomichnites strandi (most common) and Palmichnium antarticum (form A), and the traces include Cruziana sp. Didymaulichnus lyelli, Didplodichnus biformis, Planolites sp. and Rusophysus sp. The formation, >6 km thick, was deposited during semi-arid and humid climates in a terminal fan environment. The discovery of Palmichnium antarticum (form B) from the Givetian Gum Creek beds at Moona Vale Station is also reported.     

Taphonomic observations on eastern Australian Cretaceous sauropods

Cretaceous (Albian–Cenomanian) sauropod body fossils are known from the Eromanga Basin of central Queensland and Surat Basin of northern New South Wales/southeastern Queensland. Most bones are uncrushed and undistorted. Associated components of the caudal and forelimb skeleton are dominant in current collections and probably derived from more complete skeletons now lost to erosion, or yet to be exposed. Dorsal and cervical vertebrae have rarely been reported and no cranial material has yet been found. None of the Australian sauropod remains shows evidence of predation or scavenging, but at least two specimens of Wintonotitan wattsi were intimately associated with plant macrofossils allowing limited inference of their postmortem environments.     

南阳麒麟岗西汉墓中出土的后石家河文化玉鹰

1989年南阳麒麟岗西汉墓M8出土了一件后石家河文化时期减地阳线纹的玉鹰残件。根据其他遗址出土或传世的类似形制遗物,对这件器物进行研究性复原。复原后发现该件玉鹰为目前已出土的后石家河文化时期尺寸最大的圆雕玉器,为探讨后石家河文化时期的玉器传播提供了新的资料。     

Seismic evidence for fluid migration pathways from an overpressured system in the South China Sea

Overpressured systems and intense, anomalously hot fluid expulsion in the Yinggehai Basin of the South China Sea offer an opportunity to understand the history of fluid flow and the process of hydrocarbon accumulation in overpressured environments. Fluid migration pathways from overpressured compartments in the basin are largely controlled by the distribution of faults and fractures. Episodic opening of these faults are related to the dynamics of an overpressured system and tectonic movements during basin evolution. At the crests of diapiric structures, fluid expulsion is seismically imaged as chimney‐ or plume‐like features, low to middle seismic amplitudes, and intermittently chaotic and blank reflecting seismic facies. These fluid pathways are controlled by vertical faults, which commonly penetrate overpressured and overlying normally pressured zones. Fluid expulsion is also observed near the main faults, such as the No. 1 Fault at the north‐eastern margin of the basin. Investigation by sidescan sonar on onshore and offshore Hainan Island indicates that there are more than 100 gas seepages adjacent to the No. 1 Fault. Migration pathways in the diapiric structures are controlled by three types of fault and fracture. Penetrative faults formed by dextral strike‐slip movement of the Red River faults commonly occur in the centre of the diapirs, and may have been a triggering factor for the diapirism, and controlled their distribution. Hydrofractures occur in certain mud‐rich layers and may have been generated by hydraulic fracturing. Radial normal faults occur at the top of diapirs and were formed by the intrusive process. These fluid migration pathways played an important role in regional hydrocarbon accumulation.     

Isotope sourcing of prehistoric willow and tule textiles recovered from western Great Basin rock shelters and caves – proof of concept

Isotope and trace-metal analyses were used to determine the origin of plants used to manufacture prehistoric textiles (basketry and matting) from archaeological sites in the western Great Basin. Research focused on strontium (⁸⁷Sr/⁸⁶Sr) and oxygen (¹⁸O/¹⁶O) isotope ratios of willow (Salix sp.) and tule (Schoenoplectus sp.), the dominant raw materials in Great Basin textiles. The oxygen-isotope data indicated that the willow and tule used to produce the textiles were harvested from the banks of rivers or in marshes characterized by flowing water and not from lakes or sinks. The strontium-isotope data were useful in showing which plants came from the Humboldt River and which came from rivers headed in the Sierra Nevada.     

Faunal changes in farming communities from Basketmaker II to Pueblo III (A.D. 1–1300) in the San Juan Basin of the American Southwest

The San Juan Basin of the American Southwest is home to some of the best known architecture in pre-Columbian North America. Although many faunal assemblages have been reported for individual sites, there has been little synthesis of hunting and husbandry in these farming communities. In an attempt to understand changing animal usage over time in the San Juan Basin, we use three indices to investigate the usage of artiodactyls, lagomorphs and turkeys. These three taxonomic groups formed the bulk of meat diets between Basketmaker II and Pueblo III times (A.D. 1–1300). Our analysis indicates that artiodactyls declined over time in relation to lagomorphs. Turkeys increased in the northern regions when compared to lagomorphs. Cottontails increased when compared to jackrabbits over time. We suggest that as human populations increased in the San Juan Basin, artiodactyls were more intensely hunted. People then began to raise more turkeys in favorable regions, and also hunted more lagomorphs in relation to artiodactyls. Deforestation, also as a result of increased human populations, would have created conditions more favorable for cottontails than jackrabbits in many areas.