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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Sustainable management of the historic environment resource in upland peat : a study from Exmoor

Davies, Heather Joy January 2012 (has links)
UK uplands preserve a rich history of human inhabitation and environmental change through standing monuments, archaeological sites, and within peat deposits. Palaeoenvironmental remains within peat can be used to reconstruct environmental histories throughout the Holocene. Small mires in varied topographic locations can allow detailed local landscape reconstruction, setting archaeological sites in environmental context, or building up a picture of the mosaic of changing landscapes through time. Recent moves towards assessing the ecosystem services provided by different landscapes mean that, to make a case for preserving upland peatlands for the palaeoenvironmental remains they preserve, we must be able to demonstrate their archaeological potential or value. This project investigated methods for identifying the extent of this ‘hidden’ resource, as well for assessing its current condition and historic environment value, through the case study of valley, spring and soligenous mires on Exmoor. The lack of known archaeological or material culture remains from upland peatlands in the UK and on Exmoor means that the project focussed solely on the palaeoenvironmental resource. The methods used combined desk-based survey and spatially-extensive walkover survey to assess the overall extent and condition of the palaeoenvironmental resource in mires across Exmoor. Alongside this, a site-based programme of water-table monitoring and coring was undertaken to look at the effects of recent land management practices on the condition of this resource. The results demonstrated that walkover survey and peat depth probing were necessary to define the spatial extent and depth of mires, and assess mire condition. A standardised key was developed to allow the baseline mire condition survey to be repeated. The site-based study demonstrated the negative impact of water-table draw-down on the condition of palaeoenvironmental remains. However, it also demonstrated that a multiproxy approach is necessary to allow the complex palimpsest of the effects of human impact, climate change, and recent damage to mires, to be disentangled. The results of both levels of survey fed into the development of a flexible heritage valuation system for the palaeoenvironmental resource, which highlighted mires with high-potential for future investigation, whilst indicating mires which will require management intervention to prevent further losses to the resource. The datasets provided by this project will be used to identify palaeoenvironmental sampling locations for future archaeological investigations and allow heritage managers to make active contributions to the selection of sites for mire restoration. It provides a baseline survey against which future mire condition monitoring can be compared and which can be extended to other regions. It also offers a dataset against which to test or ‘ground-truth’ new methods for identifying the extent and condition of peatlands using remote-sensed data.
2

From savanna to desert : animal engravings in the changing prehistoric environment of the Wadi al-Hayat, Libyan Sahara

Guagnin, Maria January 2010 (has links)
Traditional stylistic classifications have not provided conclusive dates for the rock art of the Sahara, and the imagery can therefore not be placed securely in its cultural or environmental context. This thesis proposes a new methodology in which content and patina of the engravings are used to establish a chronological sequence, against the background of changing palaeoenvironmental conditions. This framework can then be used to explore aspects of the relationship between the rock art and the changing Holocene landscape. The engravings of the Wadi al‐Hayat, which were recently recorded by the Fezzan Rock Art Project, form the basis of this research. A total of 2466 images of animals were individually analysed and entered into a database. The depicted species are shown to reflect the local fauna, and their habitats coincide with the palaeoclimatic conditions of the central Sahara. Additionally, recent geomorphological analyses of the rock surfaces of the Messak provide a chronology for the patina, and show that the formation of each type of patina was dependent on environmental conditions. Through analyses of the animal engravings, categorised according to positively identifiable species and patina types, this thesis demonstrates a direct correlation between the content (i.e. species depicted) and patina of the engravings, and the palaeoenvironment. Both content and patina of the engravings indicate a development from wet savanna to dry savanna, and finally to desert conditions, consistent with the Holocene climatic sequence. This provides a chronological framework for the engravings and places them into a palaeoenvironmental context. The locations of the engravings of each patina group also correspond to the changing lake levels of the al‐Hayat palaeolake identified in previous palaeoenvironmental research projects, which in turn supports the chronology of the engravings. Through spatial analyses, the locations and landscapes preferred by the engravers for the creation of rock art can be identified, whilst the new chronological sequence allows us to explore changes in the cultural conventions that underlie the creation of the engravings. As well as providing a chronological framework and environmental context for the engravings for the Wadi al‐Hayat, the research presented in this thesis therefore has the potential to change our understanding of Saharan rock art.
3

Comparative Taxonomic, Taphonomic and Palaeoenvironmental Analysis of 4-2.3 Million Year Old Australopithecine Cave Infills at Sterkfontein.

Kibii, Job Munuhe 15 November 2006 (has links)
Student Number : 0001944J - PhD thesis - School of Geography, Archaeoloy nd Environmental Studies and School of Anatomical Science - Faculty of Science / The site of Sterkfontein is rich in fossil deposits spanning different time periods from as early as 4 million years to as recent as 116, 000 years. Stratigraphy, taxonomy, taphonomy, archaeology and palaeoenvironmental analysis from various infills have been under constant review as new materials are recovered from the ongoing excavations. It is the recovery of numerous new fossils that prompted a need for a review into earlier hypotheses, interpretations and conclusions arrived at by earlier researchers on the Member 4 and the Jacovec Cavern infills. New data indicates that the two infills, though spanning different time periods, share similarities but also display marked differences in taxonomy, taphonomy and palaeoenvironment. Taxonomically, the most striking difference between the two deposits is the higher frequency of taxa and species diversity within the Member 4 faunal assemblage than in the Jacovec Cavern faunal assemblage. There are nine bovid tribes represented in five subfamilies within Member 4 and six bovid tribes in three subfamilies within Jacovec Cavern. At least five primate species have been recovered from Member 4 while three primate species have been recovered from the Jacovec Cavern. Twelve carnivore species are represented in Member 4 while eleven are represented in Jacovec Cavern. Some categories of other fauna are limited to the Member 4 infill while others are limited to the Jacovec Cavern infill. Taphonomically, both assemblages are characterized by low frequencies of bone modification. These low frequencies are a result of a culmination of various agents of accumulation and varieties and intensities of postdepositional processes that impacted on the original deposited assemblage prior to recovery. The faunal assemblage in Member 4 was accumulated into the cave through a combination of voiding carnivores, “death trap” and natural death within the cave. The Jacovec Cavern fauna on the other hand was accumulated by carnivores, not in the cavern but on the surface above and within the vicinity of the cave entrance. Eventually fluvial action incorporated the surface materials, including faunal remains into the Jacovec Cavern. Palaeoenvironmental reconstruction indicates a correlation of climatic conditions similar to that derived from analysis of terrigenous sediments off the coast of Africa. For Member 4, palaeoenvironmental reconstruction indicates the existence of a mix of forest and open savannah with more emphasis on woodland, while a mosaic of open grassland and dense forest, equivalent to today’s tropical forest in Africa is suggested for the Jacovec Cavern.
4

Flora of the Ravenscrag Formation of the Big Muddy Valley, Willow Bunch Lake map area (72H), Saskatchewan

Postnikoff, Andrew Corbin Lindsay 03 February 2009
Paleocene aged beds of the Ravenscrag Formation exposed in the Big Muddy Valley of Southern Saskatchewan produce numerous plant fossils. Studies into these fossils last occurred in the 1930s. Studies into the contemporaneous Ravenscrag Butte flora of southwestern Saskatchewan have shown that the flora of these beds needed updating. Collections of specimens and stratigraphic sections were taken from the area.<p> Forty species, including two new species and seven unknowns were identified. <i>Elatocladus megasequoiae</i> n.sp. and <i>Corvirupestrobus adrielensis</i> n.sp. are both Conifers, and <i>Corvirupestrobus</i> is also a new genus. Many species were previously unknown in Ravenscrag Formation floras, including cf.<i>Lygodium</i> sp., <i>Thelypteris</i> sp., <i>Sparganium</i> sp.,<i> Paloreodoxites plicata </i> (Lesquereux) Knowlton, <i>Carya antiquorum</i> Newberry and <i>Nordenskioldia borealis</i> Heer. Two new combinations are proposed, transferring <i>Quercus praegroenlandica</i> Berry to <i>Fagopsiphyllum praegroenlandicum</i> (Berry) n. comb. and <i>Harmsia hydrocotoloidea</i> McIver and Basinger to <i>Harmsvernia hydrocotoloidea</i> (McIver and Basinger) n. comb., with <i>Harmsvernia</i> a new genus.<p> Three sub-floras are recognized for this flora. Sub-flora 1 is a conifer dominated swamp sub-flora, common to many Paleocene localities. Sub-flora 2 is a conifer dominated sub-flora suspected of being from a drier environment than florule 1. Elements of sub-flora 1 appear in sub-flora 2 and vice versa, but relative abundances differ. There is little taxonomic overlap between sub-floras 1 and 2 with sub-flora 3. Sub-flora 3 is more typical of contemporaneous localities to the south such as those of the Bear Den Member of the Golden Valley Formation (Hickey 1977), whereas sub-floras 1 and 2 are more typical of northern localities, like the Genesee locality (Chandrasekharam 1974) and Koryak Formation (Golovneva 1994). The Big Muddy Valley occurs at the ecotone between the Arctic floras and the floras of the South.<p> The taxonomy of Glyptostrobus from the Paleocene is revised as an appendix, written as a separate report. This revision is more extensive than for the other taxa of this study, utilizing materials from numerous other localities, including the Joffre Bridge Roadcut localities (Hoffman and Stockey 1999), the Smokey Tower localities (Christophel 1976) and the Buchanan Lake Formation (Basinger 1991).
5

Flora of the Ravenscrag Formation of the Big Muddy Valley, Willow Bunch Lake map area (72H), Saskatchewan

Postnikoff, Andrew Corbin Lindsay 03 February 2009 (has links)
Paleocene aged beds of the Ravenscrag Formation exposed in the Big Muddy Valley of Southern Saskatchewan produce numerous plant fossils. Studies into these fossils last occurred in the 1930s. Studies into the contemporaneous Ravenscrag Butte flora of southwestern Saskatchewan have shown that the flora of these beds needed updating. Collections of specimens and stratigraphic sections were taken from the area.<p> Forty species, including two new species and seven unknowns were identified. <i>Elatocladus megasequoiae</i> n.sp. and <i>Corvirupestrobus adrielensis</i> n.sp. are both Conifers, and <i>Corvirupestrobus</i> is also a new genus. Many species were previously unknown in Ravenscrag Formation floras, including cf.<i>Lygodium</i> sp., <i>Thelypteris</i> sp., <i>Sparganium</i> sp.,<i> Paloreodoxites plicata </i> (Lesquereux) Knowlton, <i>Carya antiquorum</i> Newberry and <i>Nordenskioldia borealis</i> Heer. Two new combinations are proposed, transferring <i>Quercus praegroenlandica</i> Berry to <i>Fagopsiphyllum praegroenlandicum</i> (Berry) n. comb. and <i>Harmsia hydrocotoloidea</i> McIver and Basinger to <i>Harmsvernia hydrocotoloidea</i> (McIver and Basinger) n. comb., with <i>Harmsvernia</i> a new genus.<p> Three sub-floras are recognized for this flora. Sub-flora 1 is a conifer dominated swamp sub-flora, common to many Paleocene localities. Sub-flora 2 is a conifer dominated sub-flora suspected of being from a drier environment than florule 1. Elements of sub-flora 1 appear in sub-flora 2 and vice versa, but relative abundances differ. There is little taxonomic overlap between sub-floras 1 and 2 with sub-flora 3. Sub-flora 3 is more typical of contemporaneous localities to the south such as those of the Bear Den Member of the Golden Valley Formation (Hickey 1977), whereas sub-floras 1 and 2 are more typical of northern localities, like the Genesee locality (Chandrasekharam 1974) and Koryak Formation (Golovneva 1994). The Big Muddy Valley occurs at the ecotone between the Arctic floras and the floras of the South.<p> The taxonomy of Glyptostrobus from the Paleocene is revised as an appendix, written as a separate report. This revision is more extensive than for the other taxa of this study, utilizing materials from numerous other localities, including the Joffre Bridge Roadcut localities (Hoffman and Stockey 1999), the Smokey Tower localities (Christophel 1976) and the Buchanan Lake Formation (Basinger 1991).
6

The stratigraphy,chronology and palaeoenvironment of The Pleistocene Cave Fill, Gladysvale Cave, South Africa

Pickering, Robyn 22 March 2006 (has links)
Master of Science - Science / The South African hominin bearing caves have yielded a wealth of early hominin and other faunal material, which has been the subject of many studies. Little work, however, has been undertaken on the cave fills themselves, as the breccias are complex, poorly stratified, highly calcified, inadequately exposed and too old to date by conventional radiometric means (Partridge, 2000). Gladysvale Cave is an exception to this, as the younger, internal deposits are well exposed from mining, are extremely well stratified, and are preliminarily dated to between 200 and 250 kyr, making this an ideal location to document the three dimensional stratigraphy and sedimentology of a cave fill fan and to test other models of cave sedimentation. The chronostratigraphic approach of Moriarty et al. (2000) was used to divide the deposit at Gladysvale into flowstone bounded units (FBU). The younger, internal deposit at Gladysvale was shown to consist of six major FBU and two minor ones, which in general occur throughout the cave. Binding flowstones are not always present, and are limited to areas directly below and in close proximity to major palaeodrip sources. The majority of sediment entered the cave through a single, central entrance and then split into two lobes around a number of stalagmitic bosses. This entrance eventually choked, and final stage sedimentation entered through a slit-like entrance across the front wall of the cave. As accommodation space inside the cave is fixed, the morphology of the units is defined by their relative position in the cave and the topography of the underlying units. Six major facies types are described, and facies changes from the proximal to distal portions of the deposit are described. Facies changes in time were controlled by the sediment supply rates. A number of intercalated flowstones and stalagmites were dated via ICP-MS Uranium-series dating, and despite problems with detrital contamination, ten reliable and robust dates were acquired, only three of which required correction for excess 232Th. The internal fan deposit is between ~570 and 7 kyr, making it both older and younger than previously thought. The dated speleothems all grew in the recovery period following a full interglacial or major inter stadial, indicating that these were periods of increased effective precipitation, during which the cave entrance was restricted to incoming clastic sediment. The dated flowstones show good concordance with the rainfall record of the Tswaing Impact Crater, and this record was used to generate an age model for the undated flowstones and intercalated breccia units. Carbon and oxygen isotope analysis of the breccias and flowstones provided further climatic control. Oxygen isotopes are invariant between flowstone and breccia, and any original signature was most likely overprinted by the residence time of the groundwater in the dolomite host rock. Carbon isotopes show more variation, and there is clear partitioning between flowstone and breccia, and ä13C values are interpreted as representing changing amounts of C3 and C4 vegetation respectively. The C4 signal for the breccias is confirmed by the presence of granular soil micropeds seen in thin sections. The succession of flowstones and breccias, the U-series dates and the stable light isotope data provide a ~600 kyr record of terrestrial climate change, which is, to date, the oldest such record for southern Africa, and shows excellent concordance with various other climate change records, both global, local and marine. The synchronicity of these records suggests a strong allocyclic control, which is attributed to changes in atmospheric circulation, in particular the size and position of the circumpolar vortex above Antarctica. A climatically controlled model for the nature and rate of sedimentation at Gladysvale Cave is proposed, in which flowstones grow during the warm, wet recovery period following full interglacials, during which C3 vegetation dominates and cave entrances are restricted. Sediments are washed into more open caves, during arid, C4 dominated conditions, corresponding to glacial periods. As this model is climatically controlled, and the Cradle of Humankind World Heritage Site is a relatively small area, the other caves in the area would have experience the same conditions, and if open at the time should contain fills of similar ages. This study has shown the value of the cave fills themselves, which are often understudied. The breccias at Gladysvale are strongly climatically controlled, being deposited only once certain climactic thresholds are crossed, hence producing a highly punctuated record. The hominin and other faunal remains from these caves should be viewed within this context. Gladysvale Cave also contains a ~600 kyr record of climate change, which will contribute to our understanding of terrestrial climatic changes and the landscape’s response to them.
7

Stigmergy in comparative settlement choice and palaeoenvironment simulation

Ch'ng, E., Gaffney, Vincent L., Hakvoort, G. 02 October 2014 (has links)
No / Decisions on settlement location in the face of climate change and coastal inundation may have resulted in success, survival or even catastrophic failure for early settlers in many parts of the world. In this study, we investigate various questions related to how individuals respond to a palaeoenvironmental simulation, on an interactive tabletop device where participants have the opportunity to build a settlement on a coastal landscape, balancing safety, and access to resources, including sea and terrestrial foodstuffs, while taking into consideration the threat of rising sea levels. The results of the study were analyzed to consider whether decisions on settlement were predicated to be near to locations where previous structures were located, stigmergically, and whether later settler choice would fare better, and score higher, as time progressed. The proximity of settlements was investigated and the reasons for clustering were considered. The interactive simulation was exhibited to thousands of visitors at the 2012 Royal Society Summer Science Exhibition at the “Europe's Lost World” exhibit. 347 participants contributed to the simulation, providing a sufficiently large sample of data for analysis.
8

Middle Pleistocene till lithostratigraphy in south Bedfordshire and the Hitchin Gap

Brownsell, Wendy Joan January 2009 (has links)
A revised lithostratigraphy and glacial history of north Hertfordshire and south Bedfordshire is based upon detailed textural data in the clay to fine gravel fraction, carbonate content, small clast lithological data and macrofabrics, derived from laboratory and field analyses of tills from 30 sites. These include four deep boreholes sunk within the Hitchin Gap. A range of statistical procedures was used, including multivariate analysis of the petrographic properties, enabling the identification of tills from two separate incursions into the Gap. A further till-type was identified in south Bedfordshire indicating an ice advance from the northwest/NNW extending at least as far east as Milton Bryan. Statistical comparison with tills in the neighbouring Vale of St. Albans suggested the presence of the Ware Member till within the Gap. Two hypotheses are suggested to explain variations in lithological content of tills north of the Chalk scarp. The first envisages ice entering the study area along the different trajectories suggested by Fish and Whiteman (2001). During the early part of the glaciation, ice reaching the west of the study area would approach from the north, crossing a shorter distance over Chalk bedrock and collecting less chalk and flint than ice moving into the eastern part of the study area. The second hypothesis invokes an incursion of ice from a northwest - NNW direction into the west of the study area, depositing a chalk-free till. This is subsequently assimilated by ice from the northeast, resulting in the final deposition of a homogeneous mixture of debris from the two advances, with a lower chalk content than tills found to the east. The outcome of either of these scenarios is a till with a low acid-soluble content and low flint/quartz ratio in the west of the study area, as found during this work. Within the Hitchin Gap, a lobe of ice, probably an early part of the northeasterly advance, deposited a lower till. This is considered to be earlier than the Ware Member till and has more variable lithological characteristics and a finer matrix that the higher tills. The latter are mainly melt-out, flow or slumped tills with occasional instances of lodgement and deformation. They represent in situ wasting of dead ice within the Gap. Surface tills in the Gap form a continuum with tills to the north and comprise mainly deformation tills, deposited by the final northeasterly re-advance of ice responsible for widespread coverage of the region, with the exception of the Chiltern Hills southwest of Hitchin. No evidence is found of more than one lithostratigraphic unit of till outside the Hitchin Gap.
9

Late Holocene environmental change at Castelporziano

Brown, Fiona S. J. January 2010 (has links)
The Mediterranean has long been recognised as an area that is particularly sensitive to climate change. It is also an area that has been impacted by human activity for millennia. Disentangling climatic and anthropogenic influences on the history of vegetation change in the Mediterranean remains an important challenge. As a contribution to this ongoing debate, this thesis explores the late Holocene environment of part of the coast in Central Italy using a multiproxy approach to investigate the archives of change preserved in dune slack deposits. Distinguishing between natural and anthropogenic signals presents a real challenge in most environmental reconstruction work; however, due to the extensive archaeological research carried out at Castelporziano, it is possible to examine human-environmental interactions in some detail. In order to understand these interactions part of the thesis examines how management has affected recent environmental changes and the current vegetation and whether there is a legacy of Roman landuse at the Castelporziano estate. The key findings of the thesis showed that dune slacks are suitable for palaeoenvironmental reconstruction with proxies such as plant macrofossils, ostracods, molluscs and bryozoans statoblasts. However, the pH and seasonality of the slacks meant proxies such as pollen were badly preserved or absent, and diatoms did not preserve due to the high levels of carbonate on site. Overall the results show the impact of the Romans on site in terms of localised eutrophication and increased fires, but with abandonment, came the formation of wet woodlands.
10

Stratigraphy and Palaeoenvironment of the Paleocene/Eocene boundary interval in the Indus Basin, Pakistan

Hanif, Muhammad January 2011 (has links)
Marine sedimentary sections across the Paleocene/Eocene (P/E) boundary interval are preserved in the Patala Formation (Upper Indus Basin) and Dungan Formation (Lower Indus Basin), Pakistan. The P/E interval of the Patala Formation is composed of limestone and shale inter-beds indicating deposition on a carbonate platform. The analysis of larger foraminifera across the P/E interval from the Patala Formation (Kala Chitta Ranges), allows the recognition of the Larger Foraminiferal Turnover (LFT). The Larger Foraminiferal Turnover (LFT) observed in the Patala Formation is associated with the PETM (Paleocene Eocene Thermal Maximum) global climatic event and allows the recognition of the P/E boundary in shallow water carbonates of the Indus Basin. This turnover is already reported from other Tethyan sections and from the Salt Range (Upper Indus Basin), Pakistan. The recognition of the LFT allows the inter-basinal and intra-basinal correlation of the P/E interval of the shallow carbonates of the Indus Basin, Pakistan. The available literature on the Paleocene-Eocene Patala and Dungan formations is used to review the planktonic foraminiferal biostratigraphy of the P/E interval. The planktonic foraminiferal zones in the P/E interval of the Indus Basin are identified and reviewed in the light of new international zonations. The planktonic foraminiferal content of the Dungan Formation allows its correlation with the Laki Formation of Rajesthan (India). Four dinoflagellate zones in the P/E interval of the Rakhi Nala section (Lower Indus Basin) are identified and correlated with international and regional zonations. The quantitative analysis of the dinoflagellate cyst assemblages together with geochemical data (i.e., carbon isotopes (organic only), C/N ratio, TOC, carbonate content) is used to reconstruct the palaeoenivronment across the P/E interval. The dinocyst assemblages in general, and the abundance of Apectodinium spp. in particular, indicate the warmer surface water conditions of the global PETM event. The dinocyst assemblages allow the local correlation of the Dungan Formation (part) of the Sulaiman Range with the Patala Formation (part) of the Upper Indus Basin and global correlation of the Zone Pak-DV with the Apectodinium acme Zone of the Northern and Southern hemispheres. The carbon isotopic excursion (CIE) associated with PETM is now globally used to identify the P/E boundary. The CIE in total organic carbon (i.e., δ13CTOC = -28.9‰) and total fine fraction organics (i.e., δ13CFF= 26.4‰) from the Indus Basin is reported for the first time. This CIE record from the Indus Basin is compared with other Tethyan sections from Egypt and Uzbekistan and is also compared with the global sections from USA (Northern hemisphere) and from New Zealand (Southern hemisphere).

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