Subsurface Stone Lines, Stone Zones, Artifact-Manuport Layers, and Biomantles Produced by Bioturbation via Pocket Gophers (Thomomys Bottae)

1989 ◽  
Vol 54 (2) ◽  
pp. 370-389 ◽  
Author(s):  
Donald L. Johnson
Keyword(s):  
Laboratory Tests ◽  
Fine Fraction ◽  
Archaeological Site ◽  
Site Formation ◽  
Maximum Diameter ◽  
Field Observations ◽  
Pocket Gophers ◽  
Subsurface Zone ◽  
Thomomys Bottae ◽  
Gravelly Soil

A prominent subsurface zone (layer) of large stones with diameters greater than 6-7 cm occurs in gravelly soil on colluvial aprons in the Lompoc area of California. The soil is mounded and churned by botta pocket gophers (Thomomys bottae). Sedimentological analyses show that the soil within and above the stone zone—and within the gopher mounds—is relatively homogeneous in fine fraction and forms a biomantle. None of the mounds contained stones with long-axis diameters greater than the maximum diameter of gopher burrows, about 6-7 cm. Larger stones gradually subside and form a stone zone. Both field observations and laboratory tests confirm that gopher bioturbation produces stone zones in coarse gravelly soil. This finding, and similar findings in two other recent studies, have important implications for interpreting archaeological site formation, and for interpreting geologic-pedologic processes inasmuch as artifact layers (and nonartifact layers) in some sites entirely may be due to nonanthropic, nongeologic, postdepositional biological agents.

scholarly journals Bothersome burrowers: tracking gopher (Thomomys bottae) time-averaging in a late-Holocene site in California

2021 ◽  
Author(s):  
Maria Viteri ◽  
Elizabeth Hadly
Keyword(s):  
Small Mammals ◽  
Late Holocene ◽  
Archaeological Site ◽  
Skeletal Remains ◽  
Time Averaging ◽  
Faunal Remains ◽  
Pocket Gophers ◽  
Thomomys Bottae ◽  
Sediment Layers ◽  
Shed Light

Understanding the taphonomic biases affecting fossil deposits is necessary in order to extract their true ecological signals. In terrestrial sites, the mixing of fossil material by mammalian bioturbators can substantially increase time-averaging, obscuring or even erasing stratification. In particular, pocket gophers (Thomomys sp.) are known to burrow in Holocene sites and thereby complicate the contextualization of faunal remains. Not only is it unclear if bones have been transported vertically by gophers, but the gophers themselves have the potential to die in their burrows, adding young skeletal remains to older deposits. We establish the degree of bias introduced by gopher remains in a late-Holocene archaeological site in Woodside, California by radiocarbon dating skeletal remains of Thomomys bottae and non-fossorial small mammals from the same stratigraphic units. The ages of T. bottae bones are younger overall, and span a wider range, than the distribution of ages from other small mammals from the same site and sediment layers. This suggests that a significant number of gopher remains have been introduced after the site’s deposition as a consequence of burrowing. These results shed light on a common taphonomic process that affects archaeological and paleontological sites, and may prompt reevaluation of faunal community reconstructions from fossil deposits impacted by gophers and other fossorial mammals.

SITE FORMATION OF THE LATE AND POTENTIALLY MIDDLE PLEISTOCENE FARRE ARCHAEOLOGICAL SITE, CHALBI BASIN, NORTHERN KENYA

2017 ◽  
Author(s):  
Mallory N. Gerzan ◽  
◽  
Gary E. Stinchcomb ◽  
Joseph V. Ferraro ◽  
Steven L. Forman ◽  
...  
Keyword(s):  
Archaeological Site ◽  
Site Formation ◽  
Middle Pleistocene ◽  
Northern Kenya

The Archaeological Record

2017 ◽  
Author(s):  
Manjil Hazarika
Keyword(s):  
Archaeological Site ◽  
Northeast India ◽  
Site Formation ◽  
Archaeological Sites ◽  
Site Formation Processes ◽  
Formation Processes ◽  
Site Structure ◽  
Reserve Forest ◽  
Ethnographic Data ◽  
Ways Of Life

This chapter elaborates the data and results of the explorations conducted in the Garbhanga Reserve Forest. The area has been intensively surveyed for the location of potential archaeological sites and the collection of ethnographic data in order to draw direct historical analogies. An ‘area-approach’ study has been conducted in order to formulate a general model for archaeological site structure, locations, geomorphic situations, and site formation processes that can be used for archaeological study in the hilly landscape of Northeast India. Present-day agricultural implements have been analysed and compared with Neolithic implements in order to reconstruct ancient farming culture by way of undertaking systematic study of modern peasant ways of life in the study area. The ideological significance of stone artefacts as ‘thunderstone’ in Northeast India and among the Karbis has also been discussed.

scholarly journals Geochronology and physical context of Oldowan site formation at Kanjera South, Kenya

2018 ◽  
Vol 156 (07) ◽  
pp. 1190-1200 ◽  
Author(s):  
P. W. DITCHFIELD ◽  
E. WHITFIELD ◽  
T. VINCENT ◽  
T. PLUMMER ◽  
D. BRAUN ◽  
...  
Keyword(s):  
Depositional Environment ◽  
Fine Fraction ◽  
Lacustrine Sediments ◽  
Site Formation ◽  
Lake Basin ◽  
Limited Evidence ◽  
Associated Fauna ◽  
Physical Context ◽  
Granulometric Analysis ◽  
Kanjera South

AbstractOldowan sites in primary geological context are rare in the archaeological record. Here we describe the depositional environment of Oldowan occurrences at Kanjera South, Kenya, based on field descriptions and granulometric analysis. Excavations have recovered a large Oldowan artefact sample as well as the oldest substantial sample of archaeological fauna. The deposits at Kanjera South consist of 30 m of fluvial, colluvial and lacustrine sediments. Magneto- and biostratigraphy indicate the Kanjera South Member of the Kanjera Formation was deposited during 2.3–1.92 Ma, with 2.0 Ma being a likely age for the archaeological occurrences. Oldowan artefacts and associated fauna were deposited in the colluvial and alluvial silts and sands of beds KS1–3, in the margins of a lake basin. Field descriptions and granulometric analysis of the sediment fine fraction indicate that sediments from within the main archaeological horizon were emplaced as a combination of tractional and hyperconcentrated flows with limited evidence of debris-flow deposition. This style of deposition is unlikely to significantly erode or disturb the underlying surface, and therefore promotes preservation of surface archaeological accumulations. Hominins were repeatedly attracted to the site locale, and rapid sedimentation, minimal bone weathering and an absence of bone or artefact rounding further indicate that fossils and artefacts were quickly buried.

scholarly journals Soil shrinkage and consolidation study on flood embankments in swamp irrigation areas

2021 ◽  
pp. 101-110 ◽  
Author(s):  
Lusmeilia Afriani ◽  
Gatot Eko Susilo ◽  
Sri Nawangrini ◽  
Iswan Iswan
Keyword(s):  
Laboratory Tests ◽  
Linear Shrinkage ◽  
Soil Samples ◽  
Field Observations ◽  
Soil Consolidation ◽  
North East ◽  
Soil Shrinkage ◽  
Embankment Height ◽  
The One ◽  
Downstream Area

Research in this paper discusses shrinking and consolidation of flood embankments soil in swamp irrigation areas. The flood embankments are made from swampy soil materials. The focus of this research is the reduction of dyke embankment height that occurs due to soil shrinkage and soil consolidation. Investigations about the time of consolidation and land subsidence that occurred on the embankment at certain periods after the embankment established were also carried out in this study. The research sites are some swamp irrigation areas in the Tulang Bawang Watershed, around North-East Lampung, Indonesia. This research was carried out by conducting laboratory tests on soil samples and field observations on the reduction in height of flood embankments in the study area. The research shows that the main cause of total decrease on the embankment is due to linear shrinkage, consolidation of soil under the embankment, an immediate subsidence, and the subsidence of the embankment themselves. Their contribution to total decrease of embankment is 42.51%, 34.48%, 18.32%, and 4.62%, respectively. Results also indicate that the ratio between the percentage of embankment consolidation in downstream area happen faster than the one in upstream area of the river.

scholarly journals Influence of Weathering on the Engineering Properties of Dacites in Northeastern Turkey

2012 ◽  
Vol 2012 ◽  
pp. 1-15 ◽  
Author(s):  
Fehmi Arikan ◽  
Nihal Aydin
Keyword(s):  
Laboratory Tests ◽  
Chemical Weathering ◽  
Engineering Properties ◽  
Open Pit ◽  
Major Influence ◽  
Content Increase ◽  
Field Observations ◽  
Loss On Ignition ◽  
Copper Mines ◽  
Weathering Grades

The purpose of this study is to investigate dacites of different weathering grades from the Cakmakkaya and Damar open-pit copper mines in northeastern Turkey based on their mineralogical, petrographical, and geomechanical characteristics. The dacites for which surveys are carried out are mainly subjected to chemical weathering as well as physical disintegration and hydrothermal alteration. Discontinuities in this rock appear to be a major influence on the spatial distribution of weathering profiles, with the intensity of weathering increasing in the plagioclase phenocrystals and microlites as the weathering grade increases. The present results show that the type and amount of clay minerals increase as the weathering grade increases. As the weathering increases, the amount of mobile oxides, such as Na2O, MgO, and CaO, decreases while Fe2O3 and the loss on ignition (LOI) content increase for most of the dacite samples. The microfracture frequency () may be a good indicator of fabric changes, and methylene blue adsorption (MBA) test and LOI may be good indicators of chemical weathering for the dacites. Geomechanical laboratory tests indicate that the strength of the samples is controlled by weathering. Field observations and mineralogical analyses show that the effects of weathering are critical for slope stability.

Early oligochaete science, from Aristotle to Francesco Redi

2011 ◽  
Vol 38 (1) ◽  
pp. 136-163 ◽  
Author(s):  
Emilia Rota
Keyword(s):  
Eighteenth Century ◽  
Seventeenth Century ◽  
Laboratory Tests ◽  
Habitat Requirements ◽  
Field Observations ◽  
Internal Anatomy ◽  
Internal Organs ◽  
Late Renaissance ◽  
Parasitic Worms

The paper reviews knowledge on earthworms from early classical times to the end of the seventeenth century. The Aristotelian view that these “imperfect” animals developed spontaneously from mud and lacked internal organs except the gut was not challenged until the late Renaissance but, by the end of the 1600s, it was overthrown. Aldrovandi and Mouffet presented field observations of sexual reproduction and specific habitat requirements. Willis demonstrated the complex internal anatomy of an earthworm. Finally Redi, based on numberless dissections, showed the existence of variations on that basic anatomical plan, which anyway remained distinct from that of parasitic worms. Through a series of controlled laboratory tests, Redi also proved that earthworms have a physiology of their own and are most sensible to water loss. In those same years, Swammerdam investigated earthworm cocoons nursing them in his room, and Tyson discovered earthworms’ hermaphroditism. Two significant interpretations of earthworm's locomotion, by Fabrici ab Aquapendente and Borelli, also belong to this period, but were both short-lived in their influence. An awareness of the ecological role of earthworms in pedogenesis and soil fertility did not emerge until the late eighteenth century.

Identifying the Brazil nut effect in archaeological site formation processes

2020 ◽  
Vol 2 (2) ◽  
pp. 267-281 ◽  
Author(s):  
David Luria ◽  
Alexander Fantalkin ◽  
Ezra Zilberman ◽  
Eyal Ben-Dor
Keyword(s):  
Archaeological Site ◽  
Site Formation ◽  
Site Formation Processes ◽  
Formation Processes ◽  
Brazil Nut ◽  
Brazil Nut Effect
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