Stratigraphy and genesis of five superposed paleosols in pre-Wisconsinan drift on Mokowan Butte, southwestern Alberta

1987 ◽  
Vol 24 (11) ◽  
pp. 2235-2253 ◽  
Author(s):  
Eric T. Karlstrom
Keyword(s):  
Surface Soil ◽  
Soil Formation ◽  
Early Pleistocene ◽  
Paleomagnetic Data ◽  
Late Pliocene ◽  
Regional Correlation ◽  
Late Tertiary ◽  
Soil Age ◽  
Semi Arid ◽  
Properties Of Soil

Five paleosols in five superposed diamicts (probably tills) on Mokowan Butte permit subdivision of pre-Wisconsinan drift and a description of Quaternary and probably late Tertiary soil-forming environments. The surface soil and upper two buried paleosols (soils 5, 4, and 3, respectively) have strongly developed, 1–5 m thick, leached, reddish, clay-rich (20–48% clay), argillic horizons overlying indurated petrocalcic, calcic, or leached B horizons. The lower two buried paleosols (soils 2 and 1) are strongly developed and have 40–150 cm thick, clay-rich (18–49% clay) argillic horizons over calcic, petrocalcic, or leached B horizons. Based on their resemblance to Paleudalfs, Paleustalfs, or Palexerults, soils 5, 4, and 3 probably formed under interglacial climates that were moister and at least 6 °C warmer than the present. Properties of soil 2 (Petrocalcic Paleustalf) and soil 1 (Typic Croboralf) imply soil formation under warm, semi-arid climates and a modern type of climate, respectively. Estimates of soil age based on degree of soil formation, paleomagnetic data, and regional correlation with dated glacial chronologies suggest soils 5 and 4 are in middle and early Pleistocene tills (= early Illinoian or Kansan and Nebraskan?), respectively, and soils 3, 2, and 1 are in late Pliocene till or diamict.

A Fossil Flora From Rafted Plio-Pleistocene Mudstones at Regatta Point, Tasmania.

1985 ◽  
Vol 33 (5) ◽  
pp. 497 ◽  
Author(s):  
RS Hill ◽  
MK MacPhail
Keyword(s):  
Early Pleistocene ◽  
Fossil Flora ◽  
The West ◽  
Late Pliocene ◽  
Late Tertiary ◽  
Cool Temperate ◽  
Successful Establishment ◽  
Pollen And Spores ◽  
The Common ◽  
Lagarostrobos Franklinii

A Late Pliocene-Early Pleistocene flora from Regatta Point on Macquarie Harbour contains pollen, cladodes, flowers and infructescences of Casuarina (s.l.), suggesting that the site of deposition was surrounded by the source plants. However, leaves and shoots of Nothofagus cunninghamii, Eucryphia, Atherosperma moschatum, Quintinia, Acacia, Lagarostrobos franklinii, Phyllocladus aspleniifolius, Podocarpus, Athrotaxis selaginoides and A. cf. cupressoides also occur, along with pollen and spores of the common rainforest species, and it can be inferred that a cool temperate rainforest was present upstream of the site of deposition. This fossil flora represents the earliest evidence to date of modern rainforest elements in Tasmania. Pollen of a number of modern sclerophyll species, including Epacridaceae, Proteaceae and Eucalyptus, is also present. The presence of a Quintinia leaf in the Regatta Point flora is evidence that some species have become extinct in Tasmania relatively recently. Extant Tasmanian rainforests evolved from more diverse Mid Tertiary rainforests, probably in response to the Late Tertiary cooling and repeated Quaternary glaciations. The same environmental vicissitudes may have also been responsible for the successful establishment of eucalypts on the west coast of Tasmania by the Late Pliocene-Early Pleistocene, resulting in a vegetation probably similar to that now present around Macquarie Harbour.

scholarly journals Millennial-scale climate change and oceanic processes in the Late Pliocene and Early Pleistocene

2001 ◽  
Vol 16 (5) ◽  
pp. 535-543 ◽  
Author(s):  
Katherine Mc Intyre ◽  
Margaret L. Delaney ◽  
A. Christina Ravelo
Keyword(s):  
Climate Change ◽  
Early Pleistocene ◽  
Late Pliocene ◽  
Millennial Scale

Controls of surface soil moisture spatial patterns and their temporal stability in a semi-arid steppe

2010 ◽  
Vol 24 (18) ◽  
pp. 2507-2519 ◽  
Author(s):  
Y. Zhao ◽  
S. Peth ◽  
X. Y. Wang ◽  
H. Lin ◽  
R. Horn
Keyword(s):  
Soil Moisture ◽  
Spatial Patterns ◽  
Surface Soil ◽  
Temporal Stability ◽  
Surface Soil Moisture ◽  
Arid Steppe ◽  
Semi Arid

Physical, chemical, and mineralogical attributes and organic fractions of biogenic aggregates of earthworms and toposequence of Inceptisol in semi-arid region

2021 ◽  
Vol 45 ◽  
Author(s):  
Eula Paula da Silva Santos ◽  
Flavia Giglianne Freitas Lima ◽  
Eulene Francisco da Silva ◽  
Diana Ferreira de Freitas ◽  
Eveline de Almeida Ferreira ◽  
...  
Keyword(s):  
Clay Minerals ◽  
Arid Region ◽  
Organic Fraction ◽  
Neem Tree ◽  
Physical Chemical ◽  
Organic Fractions ◽  
Semi Arid Region ◽  
Lower Slope ◽  
Semi Arid ◽  
Properties Of Soil

ABSTRACT Earthworms are known to improve soil fertility by altering the physicochemical properties of soil. However, the changes in properties of biogenic aggregates (produced by earthworms) in regions with different vegetation covers and soils of Inceptisol toposequence in the semi-arid region have not been studied. The objective of this work was to determine the variations of the physical, chemical, and mineralogical attributes and organic fractions of biogenic aggregates of earthworms under different vegetation covers and compare them to an Inceptisol toposequence in the semi-arid region of Pernambuco State, Brazil. For this study, four Inceptisol soil profiles were selected. The sampled points were P1-upper; P2-middle third; P3-middle third; and P4-lower slope, and the soils were collected at a depth of 0-0.20 m. The biogenic aggregates were found in the P3 samples collected from three areas with different vegetation covers: an area with mesquite tree vegetation (Prosopis juliflora [Sw] D.C.); an area with neem tree vegetation (Azadirachta indica A. Juss); and an area with forage palm and mesquite tree vegetation (Opuntia sp. and Nopalea sp.). Results indicate that the biogenic aggregates were in the form of irregular blocks with a size greater than 40 mm. As compared to Inceptisol samples, these aggregates tended to select particles of smaller diameter and exhibited higher concentrations of clay minerals. The chemical and organic fraction analysis revealed that the aggregates exhibited higher Ca2+, total organic carbon (TOC), labile and humic substances, regardless of the vegetation cover. The mineralogical analysis revealed that the action of earthworms did not change the quantity or type of clay minerals.

scholarly journals Khorbas: a Lower Palaeolithic site on Qeshm Island in the Persian Gulf

Antiquity ◽  
2017 ◽  
Vol 91 (358) ◽  
Author(s):  
Sirvan Mohammadi Ghasrian
Keyword(s):  
Persian Gulf ◽  
Early Pleistocene ◽  
Fars Province ◽  
Potential Importance ◽  
Zagros Mountains ◽  
The West ◽  
Qeshm Island ◽  
Late Pliocene ◽  
The Persian Gulf ◽  
Lower Palaeolithic

Despite the potential importance of southern Iran, and the Persian Gulf area in particular, for discussions on the dispersal of early hominins from Africa into Eurasia during the late Pliocene and early Pleistocene (Bar-Yosef & Belfer-Cohen 2001; Rose 2010), this area has remained almost unexplored until recently. Historically, Palaeolithic survey and excavations in Iran have mainly concentrated in western regions, especially the Zagros Mountains. As a result of recent studies, however, evidence for Palaeolithic sites in the southern regions of Iran, from Fars province to Qeshm Island, has greatly increased (Dashtizade 2009, 2010). Even with this improvement, no sites of Lower Palaeolithic date have yet been reported from the southern coastal areas on one of the proposed early hominin routes into Eurasia. As a result, it has been suggested that the few Lower Palaeolithic sites reported from other parts of Iran, especially in the west (e.g. Biglari & Shidrang 2006), were not populated from the south.

scholarly journals Contribution of changes in opal productivity and nutrient distribution in the coastal upwelling systems to Late Pliocene/Early Pleistocene climate cooling

2012 ◽  
Vol 8 (5) ◽  
pp. 1435-1445 ◽  
Author(s):  
J. Etourneau ◽  
C. Ehlert ◽  
M. Frank ◽  
P. Martinez ◽  
R. Schneider
Keyword(s):  
Southern Ocean ◽  
Coastal Upwelling ◽  
Atmospheric Co2 ◽  
Early Pleistocene ◽  
Silicon Isotope ◽  
Time Interval ◽  
Nutrient Distribution ◽  
Biogenic Opal ◽  
Late Pliocene ◽  
Polar Ocean

Abstract. The global Late Pliocene/Early Pleistocene cooling (~3.0–2.0 million years ago – Ma) concurred with extremely high diatom and biogenic opal production in most of the major coastal upwelling regions. This phenomenon was particularly pronounced in the Benguela upwelling system (BUS), off Namibia, where it is known as the Matuyama Diatom Maximum (MDM). Our study focuses on a new diatom silicon isotope (δ30Si) record covering the MDM in the BUS. Unexpectedly, the variations in δ30Si signal follow biogenic opal content, whereby the highest δ30Si values correspond to the highest biogenic opal content. We interpret the higher δ30Si values during the MDM as a result of a stronger degree of silicate utilisation in the surface waters caused by high productivity of mat-forming diatom species. This was most likely promoted by weak upwelling intensity dominating the BUS during the Late Pliocene/Early Pleistocene cooling combined with a large silicate supply derived from a strong Southern Ocean nutrient leakage responding to the expansion of Antarctic ice cover and the resulting stratification of the polar ocean 3.0–2.7 Ma ago. A similar scenario is hypothesized for other major coastal upwelling systems (e.g. off California) during this time interval, suggesting that the efficiency of the biological carbon pump was probably sufficiently enhanced in these regions during the MDM to have significantly increased the transport of atmospheric CO2 to the deep ocean. In addition, the coeval extension of the area of surface water stratification in both the Southern Ocean and the North Pacific, which decreased CO2 release to the atmosphere, led to further enhanced atmospheric CO2 drawn-down and thus contributed significantly to Late Pliocene/Early Pleistocene cooling.

Sign in / Sign up

Export Citation Format

Share Document