Tephrostratigraphy of the Bedded Tuff Member (Kapthurin Formation, Kenya) and the nature of archaeological change in the later middle Pleistocene

2006 ◽  
Vol 65 (3) ◽  
pp. 492-507 ◽  
Author(s):  
Christian A. Tryon ◽  
Sally McBrearty
Keyword(s):  
Volcanic Glass ◽  
Middle Stone Age ◽  
Middle Pleistocene ◽  
Tool Manufacture ◽  
Production Methods ◽  
Time Period ◽  
Volcanic Source ◽  
Geochemical Analyses ◽  
Different Sources ◽  
Kapthurin Formation

AbstractCorrelation of volcaniclastic deposits of the Bedded Tuff Member (K4) of the Kapthurin Formation (Kenya) provides the means to assess the nature of archaeological change during the later middle Pleistocene, a time period critical to human evolution but poorly represented at other African localities. Field stratigraphic evidence, and petrographic and electron microprobe geochemical analyses of volcanic glass and phenocrysts, define eight subdivisions of K4 tephra. These include a succession of deposits from a local volcanic source that erupted intermittently, as well as other tuffs likely from different sources outside the Baringo basin. Upper portions of the Bedded Tuff Member date to ∼235,000 yr. The Bedded Tuff Member is underlain by sediments that include the Grey Tuff, dated to 509,000 ± 9000 yr. The tephrostratigraphic framework defined here is used to place Acheulian and Middle Stone Age (MSA) archaeological sites in chronological order. Results show the persistence of Acheulian large cutting tool manufacture after the advent of points, considered an MSA artifact type. Two assemblages from the site of Koimilot record the appearance at ∼200,000–250,000 yr of a variety of Levallois flake production methods, an integral if incompletely understood feature of the MSA, here likely derived from local technological antecedents. Combined evidence from the tools and flake production methods suggest an incremental and mosaic pattern of change in hominin adaptive strategies during the Acheulian–MSA transition.

scholarly journals A review: hybrid simulation in forestry supply chain

2021 ◽  
Vol 912 (1) ◽  
pp. 012009
Author(s):  
N Sembiring ◽  
H L Napitupulu ◽  
M T Sembiring ◽  
A Ishak ◽  
F Irwany
Keyword(s):  
Supply Chain ◽  
Experimental Testing ◽  
Hybrid Simulation ◽  
Simulation Method ◽  
Scientific Article ◽  
Supply Chain Network ◽  
Supply Chain Optimization ◽  
Production Methods ◽  
Time Period ◽  
Forestry Sector

Abstract Changes in supply chain availability in the forestry sector can significantly change efficiency responsiveness. This forestry supply chain network involves various processes such as harvesting, energy generation, wood, paper and board production. Methods that can be used to perform supply chain optimization are hybrid modelling and simulation. Substructure techniques with experimental testing methods that target numerical component conductors with communication loop components as well as transfer systems to form an entire system commonly referred to as Hybrid Simulation. In this study, we aim to find solutions so that the supply chain network in the forestry sector is not cut off by using hybrid simulation method. Hybrid simulations used can take into account when the supply chain will run out and prevent excessive exploitation so as to repair damage and recycle the supply chain so that it is not disconnected until the time period is taken into account. Each scientific article is rigorously selected to obtain articles that align with the purpose of this research.

scholarly journals Pleistocene horses (genus Equus) in the central Balkans

2003 ◽  
pp. 55-75 ◽  
Author(s):  
Ann Forsten ◽  
Vesna Dimitrijevic
Keyword(s):  
Late Pleistocene ◽  
River Valley ◽  
Middle Pleistocene ◽  
Mountainous Area ◽  
Migration Routes ◽  
Northern Greece ◽  
The North ◽  
Time Period ◽  
Morava River ◽  
River Valleys

A review of the fossil horses of the genus Equus from the central Balkans, a mountainous area comprising Serbia and Montenegro, is presented in this paper. The time period covered by the finds is from the late Early to and including the Late Pleistocene, but the record is not complete: the dated finds are Late Pleistocene in age, while Early and Middle Pleistocene are poorly represented. The horses found resemble those from neighbouring countries from the same time period, probably showing the importance of river valleys as migration routes. The Morava River valley runs in a roughly south-to-north direction, connecting, via the Danube and Tisa River valleys the Hungarian Pannonian Plain in the north with northern Greece in the south, via the Vardar River valley in Macedonia. In Pleistocene, large mammals, including horses, probably used this route for dispersal.

On the issues related to the discoid cores

2017 ◽  
Vol 17 (1) ◽  
pp. 174-178
Author(s):  
Youcheng Chen ◽  
Tongli Qu
Keyword(s):  
Middle Stone Age ◽  
Middle Pleistocene ◽  
Middle Paleolithic ◽  
Stone Age ◽  
The West ◽  
Upper Pleistocene ◽  
Old World ◽  
Insight Into

AbstractThe discoid core and the Levallois core are important symbols of the Middle Paleolithic Age in the west of the Old World. The two types of artifacts show not only technical relationships but also differences. The discoid core can be classified into two sub-types, namely the unifacial and the bifacial classes. In China, discoid cores may have appeared in the upper Middle Pleistocene, and prevailed in the lower and middle Upper Pleistocene, which corresponded to the middle Paleolithic Age in Europe and to the Middle Stone Age in Africa. The discovery and study of discoid cores provide significant insight into the culture of the Middle Paleolithic Age in China.

scholarly journals The impact of African aridity on the isotopic signature of Atlantic deep waters across the Middle Pleistocene Transition

2012 ◽  
Vol 77 (1) ◽  
pp. 182-191 ◽  
Author(s):  
Bruno Malaizé ◽  
Elsa Jullien ◽  
Amandine Tisserand ◽  
Charlotte Skonieczny ◽  
E. Francis Grousset ◽  
...  
Keyword(s):  
Deep Water ◽  
Benthic Foraminifera ◽  
Environmental Changes ◽  
Phase Relationship ◽  
Isotopic Signature ◽  
Middle Pleistocene ◽  
Time Interval ◽  
Deep Waters ◽  
Time Period ◽  
The Impact

A high resolution analysis of benthic foraminifera as well as of aeolian terrigenous proxies extracted from a 37 m-long marine core located off the Mauritanian margin spanning the last ~ 1.2 Ma, documents the possible link between major continental environmental changes with a shift in the isotopic signature of deep waters around 1.0–0.9 Ma, within the so-called Mid-Pleistocene Transition (MPT) time period. The increase in the oxygen isotopic composition of deep waters, as seen through the benthic foraminifera δ18O values, is consistent with the growth of larger ice sheets known to have occurred during this transition. Deep-water mass δ13C changes, also estimated from benthic foraminifera, show a strong depletion for the same time interval. This drastic change in δ13C values is concomitant with a worldwide 0.3‰ decrease observed in the major deep oceanic waters for the MPT time period. The phase relationship between aeolian terrigeneous signal increase and this δ13C decrease in our record, as well as in other paleorecords, supports the hypothesis of a global aridification amongst others processes to explain the deep-water masses isotopic signature changes during the MPT. In any case, the isotopic shifts imply major changes in the end-member δ18O and δ13C values of deep waters.

Operational evaluation of volcanic source terms (volcanic ash and SO2) from inverse modelling for aviation

2020 ◽  
Author(s):  
Mariëlle Mulder ◽  
Delia Arnold ◽  
Christian Maurer ◽  
Marcus Hirtl
Keyword(s):  
Source Term ◽  
Dispersion Model ◽  
Meteorological Data ◽  
A Priori ◽  
Radar Data ◽  
Particle Dispersion ◽  
Volcanic Emissions ◽  
Volcanic Source ◽  
Computational Resources ◽  
Different Sources

<p>An operational framework is developed to provide timely and frequent source term updates for volcanic emissions (ash and SO<sub>2</sub>). The procedure includes running the Lagrangian particle dispersion model FLEXPART with an initial (a priori) source term, and combining the output with observations (from satellite, ground-based, etc. sources) to obtain an a posteriori source term. This work was part of the EUNADICS-AV (eunadics-av.eu), which is a continuation of the work developed in the VAST project (vast.nilu.no). The aim is to ensuring that at certain time intervals when new observational and meteorological data is available during an event, an updated source term is provided to analysis and forecasting groups. The system is tested with the Grimsvötn eruption of 2011. Based on a source term sensitivity test, one can find the optimum between a sufficiently detailed source term and computational resources. Because satellite and radar data from different sources is available at different times, the source term is generated with the data that is available the earliest after the eruption started and data that is available later is used for evaluation.</p>

scholarly journals New Middle Pleistocene hominin cranium from Gruta da Aroeira (Portugal)

2017 ◽  
Vol 114 (13) ◽  
pp. 3397-3402 ◽  
Author(s):  
Joan Daura ◽  
Montserrat Sanz ◽  
Juan Luis Arsuaga ◽  
Dirk L. Hoffmann ◽  
Rolf M. Quam ◽  
...  
Keyword(s):  
Homo Erectus ◽  
Middle Pleistocene ◽  
Homo Heidelbergensis ◽  
Incipient Stage ◽  
Sima De Los Huesos ◽  
Time Period ◽  
Nasal Floor ◽  
Fossil Hominins ◽  
The Right ◽  
Important Evidence

The Middle Pleistocene is a crucial time period for studying human evolution in Europe, because it marks the appearance of both fossil hominins ancestral to the later Neandertals and the Acheulean technology. Nevertheless, European sites containing well-dated human remains associated with an Acheulean toolkit remain scarce. The earliest European hominin crania associated with Acheulean handaxes are at the sites of Arago, Atapuerca Sima de los Huesos (SH), and Swanscombe, dating to 400–500 ka (Marine Isotope Stage 11–12). The Atapuerca (SH) fossils and the Swanscombe cranium belong to the Neandertal clade, whereas the Arago hominins have been attributed to an incipient stage of Neandertal evolution, toHomo heidelbergensis, or to a subspecies ofHomo erectus. A recently discovered cranium (Aroeira 3) from the Gruta da Aroeira (Almonda karst system, Portugal) dating to 390–436 ka provides important evidence on the earliest European Acheulean-bearing hominins. This cranium is represented by most of the right half of a calvarium (with the exception of the missing occipital bone) and a fragmentary right maxilla preserving part of the nasal floor and two fragmentary molars. The combination of traits in the Aroeira 3 cranium augments the previously documented diversity in the European Middle Pleistocene fossil record.

Wascana Creek Ash (Middle Pleistocene) in southern Saskatchewan: characterization, source, fission track age, palaeomagnetism and stratigraphic significance

1977 ◽  
Vol 14 (3) ◽  
pp. 357-374 ◽  
Author(s):  
J. A. Westgate ◽  
E. A. Christiansen ◽  
J. D. Boellstorff
Keyword(s):  
Mineral Assemblage ◽  
National Park ◽  
Fission Track ◽  
Volcanic Glass ◽  
The United States ◽  
Middle Pleistocene ◽  
Carbonate Content ◽  
Stratigraphic Position

Wascana Creek Ash, located close to Regina in Saskatchewan, is correlated with Pearlette ash, type O (classification of Izett et al. 1972) on the basis of its mineral assemblage, shard habit, composition of glass, titanomagnetite and chevkinite. Directions of magnetization and normal polarization of clay immediately below Wascana Creek ash further support this correlation, which is essentially confirmed by the fission track age of volcanic glass and zircon that show Wascana Creek Ash to be 0.6–0.7 Ma.Pearlette ash, type O, is derived from vents in Yellowstone National Park in Wyoming and Idaho, situated about 800 km southwest of Wascana Creek in Saskatchewan. Its air-fall tephra is widely distributed in the form of isolated lentils over the midcontinent region of the United States where stratigraphic relationships suggest a late Kansan, Yarmouth, or early Illinioan age.Wascana Creek Ash and its host clay occupy an intertill position; they rest directly on sandy till, interpreted as part of the Floral Formation, and are covered by till of the Battleford Formation. Thus, the Floral Formation in Saskatchewan may well be as old as the Kansan—that is, decidedly older than most current estimates, which favour an early Wisconsin age.The horizontal disposition and palaeomagnetic characteristics of the host clay, uniformity of carbonate content of the underlying till, and absence of local glaciotectonic features strongly suggest that the tephra and clay are in situ and not glacial erratics that have been transported as blocks from an older deposit. Furthermore, extensive reworking of the tephra from an older horizon is considered unlikely in view of minor detrital contamination, fresh glass, and conspicuous crop of glass-sheathed heavies. However, the stratigraphic position of Wascana Creek Ash should not be considered as firmly established for these observations of necessity pertain to just one locality; further occurrences must be found and studied before its stratigraphic position can be confidently defined.

scholarly journals Uneven Data Quality and the Earliest Occupation of Europe – The Case of Untermassfeld (Germany)

2017 ◽  
Author(s):  
Wil Roebroeks ◽  
Sabine Gaudzinski-Windheuser ◽  
Michael Baales ◽  
Ralf-Dietrich Kahlke
Keyword(s):  
Large Scale ◽  
Critical Evaluation ◽  
Early Pleistocene ◽  
Middle Pleistocene ◽  
Faunal Remains ◽  
Quality Of Data ◽  
Site Distribution ◽  
Time Period ◽  
Data Points

AbstractThe database regarding the earliest occupation of Europe has increased significantly in quantity and quality of data points over the last two decades, mainly through the addition of new sites as a result of long-term systematic excavations and large-scale prospections of Early and early Middle Pleistocene exposures. The site distribution pattern suggests an ephemeral presence of hominins in the south of Europe from around one million years ago, with occasional short northward expansions along the western coastal areas when temperate conditions permitted. From around 600,000-700,000 years ago Acheulean artefacts appear in Europe and somewhat later hominin presence seems to pick up, with more sites and now some also present in colder climatic settings. It is again only later, around 350,000 years ago, that the first sites show up in more continental, central parts of Europe, east of the Rhine. A series of recent papers on the Early Pleistocene palaeontological site of Untermassfeld (Germany) makes claims that are of great interest for studies of earliest Europe and are at odds with the described pattern: the papers suggest that Untermassfeld has yielded stone tools and humanly modified faunal remains, evidence for a one million years old hominin presence in European continental mid-latitudes, and additional evidence that hominins were well-established in Europe already around that time period. Here we evaluate these claims and demonstrate that these studies are severely flawed in terms of data on provenance of the materials studied and in the interpretation of faunal remains and lithics as testifying to a hominin presence at the site. In actual fact any reference to the Untermassfeld site as an archaeological one is unwarranted. Furthermore, it is not the only European Early Pleistocene site where inferred evidence for hominin presence is problematic. The strength of the spatiotemporal patterns of hominin presence and absence depend on the quality of the data points we work with, and data base maintenance, including critical evaluation of new sites, is crucial to advance our knowledge of the expansions and contractions of hominin ranges during the Pleistocene.

Paleolithic Hunter-Gatherers of Nubia

2021 ◽  
pp. 79-100
Author(s):  
Mirosław Masojć
Keyword(s):  
Middle Stone Age ◽  
Upper Paleolithic ◽  
Early Pleistocene ◽  
Middle Pleistocene ◽  
Nile Valley ◽  
Stone Age ◽  
Human Settlement ◽  
Hunter Gatherers ◽  
Lower Paleolithic ◽  
Upper Egypt

The chapter is devoted to the earliest human settlement in Nubia, which took place in the Pleistocene, with numerous references to neighboring areas, especially Upper Egypt. Paleolithic groups of humans probably appeared in Nubia in the Early Pleistocene, but well-documented sites—connected with Lower Paleolithic-Acheulean complex industries—are dated only to Middle Pleistocene (MIS 9-7). Some of the oldest Middle Stone Age (MSA) assemblages in Africa were discovered in Nubia (ca. 220 ka, MIS 7). Numerous MSA sites (ca. 220–40 ka, MIS 7-3) with predominating Levallois technology are situated within the Nile valley and the neighboring deserts, mainly in oases. The onset of Upper Paleolithic (ca. 40–20 ka, MIS 3-2) blade technology was recorded together with the oldest mining. Late Paleolithic groups of humans (20–11 ka, MIS 2), characterized by considerable diversity in the hyper-arid period, lived only in the Nile valley. Local examples of rock paintings come from that period. Pleistocene human remains from Nubia are extremely rare; they all represent H. sapiens. Cemeteries with numerous burials, some of which display evidence of violence, were also discovered in this area.

scholarly journals Measuring Social Movement Organization Populations: A Comprehensive Census of U.S. Environmental Movement Organizations

2007 ◽  
Vol 12 (3) ◽  
pp. 255-270 ◽  
Author(s):  
Robert Brulle ◽  
Liesel Turner ◽  
Jason Carmichael ◽  
J. Jenkins
Keyword(s):  
Population Level ◽  
Environmental Movement ◽  
Organizational Studies ◽  
Population Parameters ◽  
Multiple Sources ◽  
Time Period ◽  
Movement Organization ◽  
Movement Organizations ◽  
The Impact ◽  
Different Sources

Population-level analyses of SMOs typically have relied on a single source for data, most commonly the Encyclopedia of Associations (EoA). However, the validity of this procedure has been drawn into question by recent organizational studies. To examine the impact of using different sources to estimate SMO populations, we compile a comprehensive population dataset of national and regional U.S. environmental movement organizations (or EMOs) over a 100-year time period using 155 different sources. We use this data to evaluate the accuracy and selection biases in five major compilations of U.S. EMOs. The analysis shows that all single sources are selective, tapping specific sections of the environmental movement. Multiple sources are needed to capture a comprehensive population of EMOs. Researchers should be aware of the limitations of specific sources before drawing conclusions about population parameters.

Sign in / Sign up

Export Citation Format

Share Document