Dissertations / Theses: 'History of geology and palaeontology'

1

Blaj, Teodora. "Late Eocene through Oligocene calcareous nannofossils from the paleo-equatorial Pacific Ocean – taxonomy, preservation history, biochronology and evolution." Doctoral thesis, Stockholm : Department of geology and geochemistry, Stockholm university, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-27600.

Full text

APA, Harvard, Vancouver, ISO, and other styles

2

Ratcliffe, Kenneth T. "Sedimentology, palaeontology and diagenesis of the Much Wenlock limestone formation." Thesis, Aston University, 1987. http://publications.aston.ac.uk/14369/.

Full text

Abstract:

Lithofacies distribution indicates that the Much Wenlock Limestone Formation of England and South Wales was desposited on a shelf which was flat and gently subsiding in the north, but topographically variable in the south. Limestone deposition in the north began with 12m of alga-rich limestone, which formed an upward shoaling sequence. Deepening then led to deposition of calcareous silty mudstones on the northern shelf. The remainder of the formation in this area formed during a shelf-wide regression, culminating in the production of an E to W younging sandbody. Lithofacies distribution on the southern shelf was primarily controlled by local subsidence. Six bedded lithofacies are recognised which contain 14 brachiopod/bryozoan dominated assemblages, of which 11 are in situ and three consist of reworked fossils. Microfacies analysis is necessary to distinguish assemblages which reflect original communities from those which reflect sedimentary processes. Turbulence, substrate-type, ease of feeding and other organisms in the environment controlled faunal distribution. Reefs were built dominantly by corals, stromatoporoids, algae and crinoids. Coral/stromatoporoid (Type A) reefs are common, particularly on the northern shelf, where they formed in response to shallowing, ultimately growing in front of the advancing carbonate sandbody. Algae dominate Type B and Type C reefs, reflecting growth in areas of poor water circulation. Lithification of the formation began in the marine-phreatic environment with precipitation of aragonite and high Mg calcite, which was subsequently altered to turbid low Mg calcite. Younger clear spars post-date secondary void formation. The pre-compactional clear spars have features which resemble the products of meteoric water diagenesis, but freshwater did not enter the formation at this time. The pre-compactional spars were precipitated by waters forced from the surrounding silty mudstones at shallow burial depths. Late diagenetic products are stylolites, compaction fractures and burial cements.

APA, Harvard, Vancouver, ISO, and other styles

3

Vandome, Robin Cheyne. "Intellectual transformations in American geology, palaeontology and anthropology, 1850-1900." Thesis, University of Cambridge, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.608533.

Full text

APA, Harvard, Vancouver, ISO, and other styles

4

Pitchford, Andrew John. "The stratigraphy, palaeontology, and palaeoecology of the Campanian Chalk of Norfolk." Thesis, University of Liverpool, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.291739.

Full text

APA, Harvard, Vancouver, ISO, and other styles

5

Smith, Michael Paul. "Ibexian-Whiterockian (Ordovician) conodont palaeontology of east and eastern north Greenland." Thesis, University of Nottingham, 1985. http://eprints.nottingham.ac.uk/14311/.

Full text

Abstract:

Samples collected from mid-Ibexian (mid-Tremadoc) to late Whiterockian (Llandeilo) of East and eastern North Greenland have yielded a total of 9,725 identifiable conodont clements. The conodonts are referred to 54 multi-element genera and 115 species, new taxa include three genera (Macheticodus, Wandelia and Wcbcrina) and nine species (Eucharodus apion, Macheticodus lekiskus, Multioistodus? celox, Pteracontiodus armillatus, Scalpellodus? narvhalensis, Sibiriodus? kalalekus, Wandelia fuscina, Weberina candidisphaera and Weberina guyi). The faunas are coniform-dominated and generally similar to shallow water, Midcontinent Province faunas found in North America. Some degree of endemicity is indicated by the presence of species found only in the eastern Canadian Arctic Islands and Greenland. The conodonts are referred to ten biozones, of which three zones in the Ibexian are newly named (the Loxodus bransoni, Glyptoconus quadraplicatus and Oepikodus communis Zones) as are three Ibexian sub-zones (the Acodus deltatus,?Reutterodus andinus and Protoprioniodus aranda). These are all based on the previous, informal faunal divisions established in North America. In East Greenland, the oldest faunas recovered, from the base of the Cape Weber Formation on Ella Ø, are referred to the L.bransoni Zone (mid-Ibexian). Both upper and lower boundaries are, however, diachronous and on Albert Heim Bjerge, 150km to the north, the base of the formation contains conodonts of the younger G.quadraplicatus Zone. On Ella Ø, the lbexian-Whiterockian boundary occurs within the lower part of the Narwhale Sound Formation and the youngest conodonts recovered are referable to the Histiodella altifrons Zone (early Whiterockian). The youngest Ordovician conodonts recovered from East Greenland are from the Heim Bjerge Formation, directly underlying Devonian conglomerates, on C.H.Ostenfeld Nunatak; these faunas contain taxa of the Polyplacognathus sweeti Zone (late Whiterockian). In eastern North Greenland, the Wandel Valley Formation unconformably overlies Cambrian carbonates, and conodonts recovered from the base probably belong to the O.communis Zone (late lbexian). The Ibexian-Whiterockian boundary lies at or just above the lower boundary of the Upper Member and the top of the formation contains taxa referable to the Polyplacognathus friendsvillensis Zone (late Whiterockian). Contouring of the colour alteration indices (CAl) in North Greenland indicates that the isotherms are parallel to the margin of the Hazen Trough; to the east, in Kronprins Christian Land, they swing around to become parallel to the Caledonian front. Fused clusters recovered from the Cape Weber and Heim Bjerge Formations are amongst the oldest euconodont assemblages recorded. They are principally of coniform species and suggest a grasping function analogous to that of chaetognath spines.

APA, Harvard, Vancouver, ISO, and other styles

6

Martill, David Michael. "Studies on the vertebrate palaeontology of the Oxford Clay (Jurassic) of England." Thesis, University of Leicester, 1985. http://hdl.handle.net/2381/8441.

Full text

APA, Harvard, Vancouver, ISO, and other styles

7

Pether, John. "The sedimentology, palaeontology and stratigraphy of coastal-plain deposits at Hondeklip Bay, Namaqualand, South Africa." Master's thesis, University of Cape Town, 1994. http://hdl.handle.net/11427/22469.

Full text

Abstract:

Bibliography: pages 295-307.
The exposures in diamond mines on the Namaqualand west coast of South Africa provide a rare opportunity to examine a record that is normally inaccessible beneath a thick cover of aeolian sands. This study presents the main results of fieldwork in mine excavations on the farms Hondeklip and Avontuur-A, near Hondeklip Bay. Sections in the deposits were described in detail and the vertebrate and invertebrate faunas were sampled. The buried topography of the gneiss bedrock, obtained by prospecting, is complex, with the main feature consisting of a coast-parallel ridge flanking a wide palaeochannel on its landward side. Advanced kaolinitic weathering affected both the bedrock and a diamondiferous, basal kaolinitic sediment patchily preserved in the channel. The incision of the channel is related to the Oligocene regression and the basal kaolinitic sediment is interpreted as a fluvial arkose deposited in the channel. Both the bedrock and the deposit in the channel were then kaolinized during humid climatic conditions in the late Oligocene and early Miocene. Weathering-profile silcrete also developed in the basal kaolinitic sediment. It is tentatively proposed that this weathering period may be represented in the Namib Desert by the thick laterite capping Eocene sediments at Kakaoberg. Subsequently, the palaeochannel was exhumed and was ultimately filled by late Tertiary marine deposits. The marine deposits were laid down in shallowing-upwards sequences of the shore face environment. Two regressive, progradational packages (alloformations) are recognized. The older extends seawards from at least -50 m asl. and is the "45-50 m Complex" of Carrington and Kensley (1969), now called the 50 m Package. East of the channel, on the exposed coast, high-wave-energy storm-deposition in the lower shoreface dominates the preserved record. With lowering of sea-level, the bedrock ridge emerged to the seaward of the prograding palaeoshoreline, reduced the level of incident wave energy and profoundly influenced the development of sub-environments within the progradational regime. Ultimately, low-energy bay deposits filled the palaeochannel in the bedrock. On the basis of vertebrate evidence and correlation with global sea-level trends, the age of the 50 m Package is middle Pliocene. The upper facies of the 50 m Package (foreshore and upper shoreface) have been extensively removed by later subaerial erosion. The subsequent transgression truncated the seaward extent of the 50 m Package, reached ~30 m asl. and prograded seaward from that elevation. It is called the 30 m Package and combines the "29-34 m Beach" and "17-21 m Complex" of Carrington and Kensley (1969). A late Pliocene age is envisaged. The upper-shoreface facies of the 30 m Package is usually preserved, but may be disguised by pedogenesis. The diamondiferous marine gravels mined in the area are mainly lower-shoreface storm deposits and pre-existing transgressive lags and shelf deposits have generally been reworked during regression. Enigmatic, muddy and/or phosphatic units, previously called "E-stage," are patchily preserved in the base of the 50 m Package and are revealed to be distal storm deposits laid down in the transitional shoreface to offshore environment. They are part of the overlying regressive sequence, but may include a fragmentary , petrified, mixed, vertebrate remanie. Nevertheless, eroded remnants of older deposits must also occur in places.

APA, Harvard, Vancouver, ISO, and other styles

8

Sun, Weiguo. "Contributions to palaeontology and stratigraphic correlation of the late precambrian in China and Australia /." Title page, contents and summary only, 1985. http://web4.library.adelaide.edu.au/theses/09PH/09phs957.pdf.

Full text

APA, Harvard, Vancouver, ISO, and other styles

9

Pazio, Magdalena. "The late Ediacaran Agglutinated Foraminifera from Finnmark, Northern Norway." Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-183994.

Full text

APA, Harvard, Vancouver, ISO, and other styles

10

Daley, Allison C. "The morphology and evolutionary significance of the anomalocaridids." Doctoral thesis, Uppsala universitet, Paleobiologi, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-114102.

Full text

Abstract:

Approximately 600 to 500 million years ago, a major evolutionary radiation called the “Cambrian Explosion” gave rise to nearly all of the major animal phyla known today. This radiation is recorded by various fossil lagerstätten, such as the Burgess Shale in Canada, where soft-bodied animals are preserved in exquisite detail. Many Cambrian fossils are enigmatic forms that are morphologically dissimilar to their modern descendants, but which still provide valuable information when interpreted as stem-group taxa because they record the actual progression of evolution and give insight into the order of character acquisitions and homologies between living taxa. One such group of fossils is the anomalocaridids, large presumed predators that have had a complicated history of description. Their body has a trunk with a series of lateral lobes and associated gills, and a cephalic region with a pair of large frontal appendages, a circular mouth apparatus, stalked eyes and a cephalic carapace. Originally, two taxa were described from the Burgess Shale, Anomalocaris and Laggania, however data presented herein suggests that the diversity of the anomalocaridids was much higher. Newly collected fossil material revealed that a third Burgess Shale anomalocaridid, Hurdia, is known from whole-body specimens and study of its morphology has helped to clarify the morphology and systematics of the whole group. Hurdia is distinguished by having mouthparts with extra rows of teeth, a unique frontal appendage, and a large frontal carapace. Two species, Hurdia victoria and Hurdia triangulata were distinguished based on morphometric shape analysis of the frontal carapace. A phylogenetic analysis placed the anomalocaridids in the stem lineage to the euarthropods, and examination of Hurdia’s well-preserved gills confirm the homology of this structure with the outer branches of limbs in upper stem-group arthropods. This homology supports the theory that the Cambrian biramous limb formed by the fusion of a uniramous walking limb with a lateral lobe structure bearing gill blades. In this context, new evidence is present on the closely allied taxon Opabinia, suggesting that it had lobopod walking limbs and a lateral lobe structure with attached Hurdia-like gills. The diversity of the anomalocaridids at the Burgess Shale is further increased by two additional taxa known from isolated frontal appendages. Amplectobelua stephenensis is the first occurrence of this genus outside of the Chengjiang fauna in China, but Caryosyntrips serratus is an appendage unique to the Burgess Shale. To gain a better understanding of global distribution, a possible anomalocaridid is also described from the Sirius Passet biota in North Greenland. Tamisiocaris borealis is known from a single appendage, which is similar to Anomalocaris but unsegmented, suggesting this taxon belongs to the arthropod stem-lineage, perhaps in the anomalocaridid clade. Thus, the anomalocaridids are a widely distributed and highly diverse group of large Cambrian presumed predators, which provide important information relevant to the evolution of the arthropods.

APA, Harvard, Vancouver, ISO, and other styles

11

Bull, Elizabeth Eleanor. "Geology and palaeontology of the Telychian (Silurian), Reservoir Formation of the North Esk inlier, near Edinburgh, Scotland." Thesis, Open University, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.295571.

Full text

APA, Harvard, Vancouver, ISO, and other styles

12

Komarower, Patricia 1950. "The development of vertebrate palaeontology in China during the first half of the twentieth century." Monash University, School of Geosciences, 2002. http://arrow.monash.edu.au/hdl/1959.1/9337.

Full text

APA, Harvard, Vancouver, ISO, and other styles

13

Harris, William B. "The geologic history of Rock Canyon, Utah : a virtual trip /." CLICK HERE for online access, 2002. http://www.geology.byu.edu/faculty/rah/slides/Rock%20Canyon/Home.htm.

Full text

Abstract:

Thesis (M.S.)--Brigham Young University. Dept. of Geology, 2002.
Web site works as of 02/10/03. Consult BYU Dept of Geology for URL changes in future. Includes bibliographical references (leaves 8-9). Also available via Internet.

APA, Harvard, Vancouver, ISO, and other styles

14

Van, Sittert Sybrand Jacobus. "Ontogenetic allometry of the postcranial skeleton of the giraffe (Giraffa camelopardalis) with application to giraffe life history evolution and palaeontology." Thesis, University of Pretoria, 2015. http://hdl.handle.net/2263/53314.

Full text

Abstract:

Giraffes (Giraffa camelopardalis) have evolved into a unique and extreme shape. The principle determinant of its shape is the skeleton and the overarching theme of the study was to describe how this shape is achieved throughout ontogeny. Accordingly, the study had three main objectives: 1) To describe the growth of the giraffe postcranial skeleton allometrically, 2) To interpret the allometric patterns described in an evolutionary and functional sense and 3) To reconstruct the size and shape of the extinct Giraffa sivalensis using, if feasible, allometric equations obtained in this study. Secondary objectives were to a) establish if sexual dimorphism was evident in G. camelopardalis and b) determine if growth patterns in the foetus differed from those in postnatal G. camelopardalis. Data were collected from giraffes culled as part of conservancy management in Zimbabwe. The sample included 59 animals from which vertebral dimensions were taken in 48 animals and long bone dimensions in 47 animals. Body masses ranged from 21 kg to 77 kg in foetuses and 147 kg to 1412 kg postnatally, representing 29 males and 30 females. In addition to body mass, external body dimensions were recorded from each animal. Each vertebra and unilateral long bone was dissected from the carcasses and cleaned, after which dimensions were measured with a vernier calliper, measuring board or measuring tape. Vertebral dimensions measured included body (centrum) length, height and width as well as vertebral spinous process length. Long bone dimensions included length, two midshaft diameters and circumference. Allometric equations (y=bxk) were constructed from the data, with special interest in the scaling exponent (k) to illustrate regions of positively allometric, isometric or negatively allometric growth. In the first series of analyses the growth patterns of the components of the postcranial axial skeleton were analysed. The adaptations in vertebral growth to create and maintain extraordinary shape were identified as disproportionate elongation of the cervical vertebrae after birth, increasing cross sectional diameters of the cervical vertebrae from cranial to caudal and positively allometric spinal process growth. The theory of sexual selection as a driver for neck elongation in giraffes was brought into question by showing that male and female vertebral elongation rates are similar relative to increases in body mass. The second series of analyses described the growth pattern of the long bones of the appendicular skeleton. The allometric exponents seemed unremarkable compared to the few species described previously, and it was shown that the giraffe appendicular skeleton does not elongate in the dramatic way the neck does. Limbs at birth, after lengthening with positive allometry in utero, are already elongated and slender in shape and a further increase in the gracility of the bones is either not possible or not desirable. This result implies that it is neck elongation rather than leg elongation that is the dominant factor in the evolution of the giraffe shape. Nevertheless, the front limb bones and especially the humerus may show responsiveness to increasing high loads and/ or bending moments, which may be caused by the neck mass which increases with positive allometry, or with behaviours such as splaying the forelegs during drinking. In the third component of the study ontogenetic allometric equations in extant giraffes were applied to the remains of an extinct giraffid, G. sivalensis. The procedure was unusual as it employed ontogenetic regressions instead of the more commonly used interspecific regressions. The appropriateness of each equation to estimate body mass was evaluated by calculating the prediction error incurred in both extant giraffes and okapis (Okapia johnstoni). It was concluded that, due to body shape, ontogenetic equations were adequate and perhaps preferable to interspecific equations to estimate proportions in Giraffa species. This analysis showed that G sivalensis was smaller than extant giraffes and weighed around 400 kg (range 228 kg 575 kg), with a neck length of about 147 cm and a height of 390 cm. There may be evidence of sexual dimorphism in this species, with males being about twice the body weight of females. However, if sexual dimorphism was not present and all the bones were correctly attributed to this species, then G. sivalensis had a slender neck with a relatively stocky body. In conclusion, this study established ontogenetic regression equations for the skeleton of an animal of which the body shape seems to be at the extreme limits of mammalian possibility. The value of the current study lies especially in its sample size and quality, which included an unprecedented number of giraffe body masses, vertebral and long bone dimensions. This dataset had applications in the giraffe s evolutionary biology, palaeontology and even ecology. Future studies still need to compare the findings from giraffe growth with similar data from other taxa, especially those with long legs and necks. Specifically, it would interesting to determine if positively allometric neck growth combined with isometric leg growth is found in other mammalian species. In addition, the strength of giraffe long bones and vertebrae needs to be investigated with more accuracy using parameters like second moment of area. Lastly, further palaeontological studies on other giraffid sizes are necessary to validate the current and future interpretations of fossil giraffid findings.
Thesis (PhD)--University of Pretoria, 2015.
tm2016
Production Animal Studies
PhD

APA, Harvard, Vancouver, ISO, and other styles

15

Bullock, Michelle. "Holocene sediments and geological history, Woolley Lake, near Beachport, South Australia /." Adelaide : Thesis (B. Sc.(Hons)) -- University of Adelaide, Dept. of Geology and Geophysics, 1994. http://web4.library.adelaide.edu.au/theses/09SB/09sbb938.pdf.

Full text

APA, Harvard, Vancouver, ISO, and other styles

16

LaFonte, Christopher John. "Fluid History of the Western Maryland Piedmont." Bowling Green State University / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1435339052.

Full text

APA, Harvard, Vancouver, ISO, and other styles

17

Hannon, Gina E. "The use of plant macrofossils and pollen in the palaeoecological reconstruction of vegetation /." Alnarp : Swedish Univ. of Agricultural Sciences (Sveriges lantbruksuniv.), 1999. http://epsilon.slu.se/avh/1999/91-576-5640-1.pdf.

Full text

APA, Harvard, Vancouver, ISO, and other styles

18

Stein, Martin. "Evolution and taxonomy of Cambrian arthropods from Greenland and Sweden." Doctoral thesis, Uppsala University, Department of Earth Sciences, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-9301.

Full text

Abstract:

Arthropods have a rich fossil record spanning the Phanerozoic. Biomineralized forms such as the extinct trilobites are particularly common and are proven index fossils for biostratigraphy. Forms with an unmineralized cuticle are more rare, preserved only in so called konservat lagerstätten. Cambrian strata of Greenland have yielded rich trilobite faunas with potential for intercontinental correlation of Cambrian strata, but also an exceptionally preserved fauna, the Sirius Passet Lagerstätte. The first part of this thesis is concerned with trilobite biotratigraphy of the provisional Cambrian Series 2 in Greenland. The second part is concerned with exceptionally preserved arthropods from the Sirius Passet Lagerstätte, but also from 'Orsten' deposits from the Cambrian of Sweden.

Perissopyge phenax occurs in the Henson Gletscher and Paralleldal formations spanning the Series 2 and 3 boundary interval in North Greenland. It also occurs in the Sekwi Formation of Yukon Territory, demonstrating that the species may hold potential for correlation within Laurentia. An indeterminate species of Perissopyge is shown to occur in the Ella Island Formation of North-East Greenland together with Olenellus cf. hanseni, which is similar to Olenellus cf. truemani described from the Henson Gletscher Formation. If this correlation is further corroborated it would offer a first tie-point for the An t'Sron Formation of North-West Scotland which yields Fritzolenellus lapworthi, herein reported for the first time from the Bastion Formation which underlies the Ella Island Formation.

Oelandocaris oelandica from ‘Orsten’ deposits in the Cambrian series 3 and 4 boundary interval in Sweden is an early representative of the Crustacean stem lineage. Kiisortoqia avannaarsuensis is a new arthropod from the Sirius Passet Lagerstätte with robust antennulae strikingly similar to the 'raptorial' limb of the problematic anomalocaridids. The ventral morphology of the 'bivalved' Isoxys volucris is described for the first time and compared with other species assigned to Isoxys from Cambrian lagerstätten around the world. Finally, Siriocaris trolla, is a new arthropod that similarities with trilobites and certain ‘trilobitomorphs’ but seems to lack important synapomorphies of these taxa, though this may be due to preservational limitations in the material at hand.

APA, Harvard, Vancouver, ISO, and other styles

19

Widdowson, Mike. "The uplift history of the Western Ghats, India." Thesis, University of Oxford, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.304833.

Full text

APA, Harvard, Vancouver, ISO, and other styles

20

Ventris, P. A. "Pleistocene environmental history of the Nar Valley, Norfolk." Thesis, University of Cambridge, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.372911.

Full text

APA, Harvard, Vancouver, ISO, and other styles

21

Fossitt, Julie A. "Holocene vegetation history of the Western Isles, Scotland." Thesis, University of Cambridge, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.291744.

Full text

APA, Harvard, Vancouver, ISO, and other styles

22

Redwine, Joanna R. "The Quaternary history of Mohawk Valley, northeastern California." Thesis, University of Nevada, Reno, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=3608776.

Full text

Abstract:

Mohawk Valley is an inter montane basin with a rich Quaternary record, located at the northernmost end of the Sierra Nevada Mountains in northeastern California. Geologic mapping of surficial deposits, stratigraphy, tephrochronology, geomorphology, and soil development were used to interpret the past 740 ky of Quaternary history of Mohawk Valley. The robust tephrochronologic record within Mohawk Valley includes twenty-six different tephras and sixty-seven tephra beds that range in age from 740 to 7 ka. Geochemical analyses and correlations with previously identified volcanic tephras have resulted in revised age estimates for tephra beds distributed within, and beyond, Mohawk Valley.

The tephra beds were deposited in lacustrine deposits of Mohawk Lake. Elevations of shorelines and minimum lake-levels based on elevations of waterlain tephra beds were used to reconstruct the history of Mohawk Lake. Mohawk Lake began to fill prior to 740 ka and continued to fluctuate, but overall rise, until after 175-235 ka when the lake reached the sill elevation, began to spill to the west, then incrementally lower and empty by ~7 ka. Throughout this period, there were at least five, and up to nine, different generations of glacial deposits that extended towards Mohawk Lake. These glacial deposits have been mapped, their soil development and weathering properties characterized, and ages estimated based on stratigraphic relations with tephra beds deposited within Mohawk Lake deposits. This mostly continuous, 740 ky record of sedimentation has enormous potential to examine paleoclimate in this area from any of a number of paleoclimate proxies.

The interpretation that a deep lake existed in Mohawk Valley requires a mechanism to allow for deposition and preservation of organic-rich deposits in deep water. Mohawk Lake was likely a meromictic lake, a setting that leads to an anoxic environment that can preserve organic-rich sediments such as those found in Mohawk Valley. In addition, shorelines around Mohawk Valley and across much of the Mohawk Valley Fault Zone are at consistent elevations suggesting there is not a significant vertical component of faulting since 175-235 ka, and maybe since 570-610 ka. This indicates a change from the history of subsidence since the early Pliocene.

APA, Harvard, Vancouver, ISO, and other styles

23

Mager, Stephanie M. Steltenpohl Mark G. "The Late- to Post-Caledonian extensional history of Northwest Hinnøy, North Norway." Auburn, Ala., 2005. http://repo.lib.auburn.edu/2005%20Summer/master's/MAGER_STEPHANIE_56.pdf.

Full text

APA, Harvard, Vancouver, ISO, and other styles

24

Simonis, Alan F. III. "Burial History and Thermal Maturity of the Chattanooga Shale, Northwestern Alabama." Thesis, University of Louisiana at Lafayette, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=1557577.

Full text

Abstract:

The Chattanooga Shale is a petroleum source rock within the Black Warrior Basin. Several attempts have been made to exploit this formation for unconventional shale gas. However, past studies of the Chattanooga indicate an area of the shale should produce liquid hydrocarbons. This paper expands upon the previous work by using old data to create a new model for the burial history and thermal maturation of the Chattanooga Shale. This new basin model incorporates formation lithologies, ages, thicknesses, and thermal maturity indicators. The long history of the Black Warrior Basin includes a significant period of unroofing. Part of the model seeks to estimate the thickness of the missing section. The study also addresses complex maturation patterns observed in the basin by previous workers. The author concludes that an oil window exists in the Chattanooga Shale.

APA, Harvard, Vancouver, ISO, and other styles

25

Dowling, Lesley M. "Deglacial climatic history recorded in sediments of the Rockall Trough." Thesis, University of Cambridge, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.333278.

Full text

APA, Harvard, Vancouver, ISO, and other styles

26

Sharma, Milap Chand. "Quaternary history and landscape evolution of NW Garhwal, central Himalaya." Thesis, Royal Holloway, University of London, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.242051.

Full text

APA, Harvard, Vancouver, ISO, and other styles

27

Satterfield, Dorothy Ann. "Sedimentary history of a senonian foreland basin, Languedoc, southern France." Thesis, University of Oxford, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.260757.

Full text

APA, Harvard, Vancouver, ISO, and other styles

28

Creak, Susan. "The late Quaternary history of the River Erme, south Devon." Thesis, University of Plymouth, 1991. http://hdl.handle.net/10026.1/1847.

Full text

Abstract:

This thesis examines a typical 'drowned* river valley of south-west England. The River Erme drains southern Dartmoor and, in common, with other rivers of the region, has a buried channel graded to c. -50m OD. The channel has been infilled with a variety of sediments, of which the top 6-7m have been analysed for this study. Augered cores have been collected from the modern floodplain and salt marsh areas in the lower part of the valley and have been studied using particle size, diatom, molluscan and radiocarbon analyses. The main sediment types recovered include a fine silt unit representing the most recent phase of fluvial deposition, which overlies variable horizons of fluvial granitic sands and gravels and brackish organic sands and silts. These are, in places, replaced at depth by shelly silts, sands and gravels deposited under more estuarine and marine conditions. The organic layer has been radiocarbon dated to between 1000 and 2000 years BP and has been correlated with a former area of marshland recorded in the tithe maps of the region. It is suggested that the Erme valley was previously more estuarine than today and that alluviation and infilling of the Erme's channel in the last 1000-2000 years has been aided by forest clearance and tin mining on Dartmoor. All of the sediments recovered from the buried channel are derived from local sources of bedrock and have probably been deposited in the last 4000-6000 years. Evidence from the tithe maps suggests that the channel has been stable in the past 200 years. This work seeks to contribute to the Quaternary knowledge of the south-west of England, and because of the paucity of data concerning these burled rock channels, makes this study of the River Erme a preliminary model against which other rivers in the South West may be compared.

APA, Harvard, Vancouver, ISO, and other styles

29

McCann, James G. P. "Petrology and diagenetic history of the Hallstatt Limestone (Alpine trias)." Thesis, Queen's University Belfast, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.317104.

Full text

APA, Harvard, Vancouver, ISO, and other styles

30

Lewis, C. L. E. "Petrogenesis and thermal history of the Kunlun batholith, northern Tibet." Thesis, Open University, 1988. http://oro.open.ac.uk/54368/.

Full text

Abstract:

The Kunlun Terrane is the most northerly of the several microplates that comprise the Tibetan Plateau. Geochronological data from the Kunlun batholith defines three distinct periods of intrusion at 390 Ma, 250 Ma and 190 Ma. A model is presented whereby the Devonian intrusions are considered to be related to a collision event between the Kunlun and Tarim Terranes, which were part of Gondwanaland and situated in the southern hemisphere at this time. It is proposed that in the region of the 1985 Tibet Geotraverse route, the Golmud Fault represents the Kunlun- Qinling suture line along which the two plates collided. Break-up of this part of Gondwanaland, which proabably also included the Qiangtang, Lhasa and Indian plates, occurred during the Permian along the Zangbo and Jinsha suture lines. Continental rifting was followed by a prolonged period of northward subduction of the Qiangtang Terrane beneath the Kunlun Terrane. This resulted in formation of the Permian batholith, and the massive Songban-Ganzi accretionary prism. Subduction culminated in collision at about 200 Ma. Post tectonic granites were emplaced around 190 Ma. Initial Sr ratios for the granitoids range from .7074 to .7130, and support the geochemical modelling which suggests that they have been derived from melting midcrustal sources. Only the Devonian Wanbaogou pluton may have resulted from anatexis of upper crustal sediments. A reset biotite age of 120 Ma from a pluton cut by the Xidatan Fault, supports sedimentalogical evidence which indicates a major reactivation of thrust faults in the area, as a result of collision between the Lhasa and Qiangtang Terranes during the Cretaceous. Apatite fission track ages from plutons north of the Golmud Fault also document this uplift event. A 100 Ma period of quiescence ensued, during which the Kunlun Terrane cooled extremely slowly until a state of thermal equilibration was reached. The collision of India with Tibet at 45 Ma thickened the Tibetan crust and resulted in further reactivation of faults in the Kunlun Terrane. Apatites from the granites between the Golmud and Xidatan faults give mixed ages around 20 Ma. It is calculated that uplift in this region, as a result of the Himalayan collision, could have been as recent as 8 Ma.

APA, Harvard, Vancouver, ISO, and other styles

31

Liu, Qunling. "Post mid-Cretaceous sequence stratigraphy and depositional history of northeastern Gulf of Mexico /." Digital version accessible at:, 2000. http://wwwlib.umi.com/cr/utexas/main.

Full text

APA, Harvard, Vancouver, ISO, and other styles

32

Fan, Chaojun. "Revealing the hydrological history of Mars." Online access for everyone, 2008. http://www.dissertations.wsu.edu/Dissertations/Spring2008/Chaojun_Fan_032808.pdf.

Full text

APA, Harvard, Vancouver, ISO, and other styles

33

Harwood, David Michael. "Diatom Biostratigraphy and Paleoecology with a Cenozoic History of Antarctic Ice Sheets." The Ohio State University, 1986. http://rave.ohiolink.edu/etdc/view?acc_num=osu1394723672.

Full text

APA, Harvard, Vancouver, ISO, and other styles

34

Nodwell, Byron J. "Sedimentology, stratigraphy and depositional history of the Falher F conglomerate trend, Alberta, Canada." Thesis, McGill University, 2004. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=81368.

Full text

Abstract:

Detailed sequence stratigraphic analyses indicate that the lower Cretaceous Falher F unit is made up of 4 sandy/pebbly prograding parasequences labeled F1, F2, F3, and F4. Of the parasequences only F3 has a significant (>2m) thickness of conglomerate. Vertical lithological successions through a conglomeratic section suggest that the F3 pebbles were deposited on the upper shoreface and foreshore as part of a conformable, shoaling-upwards package of rocks. Detailed mapping, using core, well logs, production data and 3-D seismic, show that the conglomerates form a 4 km wide linear body deposited along a linear topographic trend. This topographic trend coincides with the northern edge of the underlying upper Devonian Gold Creek (Smokey) reef trend. Furthermore, the longshore termination of the conglomerate is located at a NW-SE trending structural feature that was active during Falher F deposition.
Two models could explain the development of a thick conglomerate buildup along a linear topographic step. The first suggests that southward (transgressive) movement of a pebbly barrier was halted at the topographic feature. The second suggests that when the F3 parasequence shoreline arrived at the topographic step progradation rates slowed significantly. (Abstract shortened by UMI.)

APA, Harvard, Vancouver, ISO, and other styles

35

Burbidge, Susan M. (Susan Margot) Carleton University Dissertation Earth Sciences. "Holocene environmental history of lake Winnipeg; thecamoebians and stable lead isotopes." Ottawa, 1997.

Find full text

APA, Harvard, Vancouver, ISO, and other styles

36

Zin, Ismail Che Mat. "Tertiary tectonics and sedimentation history of the Sarawak Basin, east Malaysia." Thesis, Durham University, 1996. http://etheses.dur.ac.uk/5198/.

Full text

Abstract:

A seismic stratigraphic study of the regional lines for the offshore Sarawak area was undertaken with the aim of understanding the tectonics and sedimentation history of the hydrocarbon prolific Sarawak Basin. The aim here is to develop a workable stratigraphic scheme, a model of the sedimentation history of the basin, a model for Tertiary tectonics, and an analysis of the subsidence history of the basin. Six unconformities have been identified within the Tertiary sedimentary succession, based on seismic reflection and well data. Some unconformities coincide with eustatic sea-level falls; others are probably tectonic in origin. An alternative stratigraphic scheme for the Sarawak Basin was developed by subdividing the whole Tertiary succession into seven sequences. Palaeoenvironment maps of the basin document the interaction of tectonics and sedimentation commencing in late Oligocene times. Deposition started with a NW-SE coastline and a broad coastal plain, almost perpendicular to the present-day coastline (NE-SW) developed during late Miocene times. The maps illustrate the likely distribution of Sarawak Basin source and reservoir rocks which will help in effective planning for future exploration in the area. The Sarawak Basin formed as a result of NW-SE trending right lateral fault movement during late Oligocene to Pliocene times. This dextral movement was responsible for creating the NW-SE coastline and divided the offshore Sarawak area into two sub-basins. Deposition and preservation of coastal plain and shallow-marine sediments continued in the eastern area while the western area remained as a 'high' until late Miocene times and subsided during late Early to Middle Miocene. The dextral strike-slip movement which controlled the evolution of the Sarawak Basin is sub-parallel to a number of lineaments elsewhere in Sarawak. The timing of movement suggests a progressive younging in an eastward direction. Basin modelling suggests that the Sarawak Basin was characterised by rapid subsidence in the early stage of basin formation with a high stretching factor and episodic movements. This suggests that the basin did not form as a foreland basin nor as a typical rift basin, but indicates a strike-slip origin. Supplementary evidence for this is provided by the findings of the regional seismic stratigraphic study, which suggests that the whole onshore area of Sarawak and northern Borneo was subjected to strike-slip tectonism during Tertiary times. The driving force may have been initiated by the lateral movement between the Sundaland and South China Continental blocks, probably due to collision between Indian and Asian plates during the Middle Tertiary, continuing with the opening of the South China Sea during the Oligocene. The end result of tectonism in the region, however, is believed to be the combination of strike-slip movements and the counter-clockwise rotation of Borneo during the Oligo-Miocene. The superiority of the proposed strike-slip tectonic model over the present subduction model is the capability to explain most of the geological phenomena, including the absence of evidence for any subduction taking place in the area. The findings of this study should contribute towards a better understanding of the tectonics of the area which will be able to provide information on the development of structural traps for hydrocarbon plays that are believed to have formed by strike-slip tectonism.

APA, Harvard, Vancouver, ISO, and other styles

37

Cartwright, Ian. "The geological history of the Lewisian complex at Stoer, NW Scotland." Thesis, Aberystwyth University, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.309457.

Full text

APA, Harvard, Vancouver, ISO, and other styles

38

Basa, Tilottama. "The petrology and history of the Holocene sedements of Dungeness, Kent." Thesis, University College London (University of London), 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.268793.

Full text

APA, Harvard, Vancouver, ISO, and other styles

39

Lebreiro, Susana Martin. "Sedimentation history off Iberia : Tore Seamount, Tagus and Horseshoe Abyssal Plains." Thesis, University of Cambridge, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.363098.

Full text

APA, Harvard, Vancouver, ISO, and other styles

40

Lageard, Jonathan G. A. "Vegetational history and Palaeoforest reconstruction at White Moss, south Cheshire, UK." Thesis, Keele University, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.317600.

Full text

APA, Harvard, Vancouver, ISO, and other styles

41

Ksiazkiewicz, Allison Ann. "Geology and neoclassical aesthetics : visualising the structure of the earth in late eighteenth- and early nineteenth-century Britain." Thesis, University of Cambridge, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.607907.

Full text

APA, Harvard, Vancouver, ISO, and other styles

42

Davies, James R. "The origin, structural style, and reactivation history of the Tabbernor Fault zone, Saskatchewan, Canada /." Thesis, McGill University, 1998. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=21534.

Full text

Abstract:

The Tabbernor Fault zone (TFZ) in Saskatchewan is a >1500km geophysical, topographic and geological lineament that trends approximately northward along the province's eastern boundary. Detailed field mapping and petrographic analyses, coupled with remote sensing and geophysical evidence have shown that the TFZ is a fundamental structure within the Trans-Hudson Orogen (THO), separating and offsetting several lithotectonic domains.
Earliest deformation preserved within the TFZ in the Wollaston Lake area is the transposition of a regional gneissic foliation onto a northeast-trending flattening plane, within north-trending sinistral shear zones. The transposed fabric is characterized by folded and attenuated remnants of the gneissic foliation, together with boudinaged leucogranitic sheets and dykes. Within these shear zones a shear fabric is developed parallel to the margins in several locations. The shear fabric offsets all earlier foliations with consistent sinistral offset. Adjacent to the shear fabric, structures are reoriented to lie dose to the shear plane.
The fault and its associated structures controlled the intrusion of granitic and pegmatitic dykes which were subsequently weakly deformed.
Brittle overprinting of ductile fault features is widespread. Sedimentary features, apatite fission track data, and uranium mineralogical studies all show that the TFZ was reactivated at least twice in Phanerozoic times. (Abstract shortened by UMI.)

APA, Harvard, Vancouver, ISO, and other styles

43

Kiconco, Lyoidah. "The Semliki Basin, Uganda : its sedimentation history and stratigraphy in relation to petroleum accumulation." Master's thesis, University of Cape Town, 2005. http://hdl.handle.net/11427/8656.

Full text

Abstract:

Includes bibliographical references (leaves 140-147).
The Semliki Basin is covered by sediments that represent the Middle Miocene to Recent, which are described from outcrop and well data, underlain by possible Jurassic or Permo-Triassic to Early Tertiary sediments, which rest unconformably on Basement, described from seismic data. Thin-section analysis of selected samples, collected from the ﬁeld, has shown that sandstones from the Semliki Basin are predominantly composed of quartz, potassium feldspars and plagioclase feldspars with subordinate clay minerals. Accessory minerals, such as micas (biotite and muscovite), heavy minerals, garnet and epidote, are present in minor amounts. This mineralogy indicates that the sediments have a granitic and gneissose origin, related to continental-block provenances. The X-ray diffraction scans of bulk samples reveal that the mudrocks/claystones are dominated by clay minerals with subordinate quartz, feldspars and calcite. The clay minerals include illite, illite-smectite, kaolinite, montmorillonite, illite-monnnorillonite, and mica with mixed layer illite-smectite and illite layers dominating. The clay minerals in the sediments were interpreted to be as a result of weathering of feldspars and volcaniclastic sediments. Authigenic minerals such as anatase and jarosite and secondary precipitates such as calcite and gypsum have also been interpreted as oxidation products of sulphides in the sediments. The study has allowed a better understanding of the stratigraphic relationship of the different rock units that are exposed on outcrop, those encountered in the wells, plus a section interpreted from seismic data. In general, the depositional environment of the sediments in the Semliki Basin is ﬂuvial-lacustrine/deltaic showing signiﬁcant variations in gamma-ray character, which reﬂect the water-level changes and river interactions through the depositional period and the inﬂuence of rifting tectonics on sediment deposition through time and space. The sediments in the Semliki Basin represent a petroleum play for hydrocarbon accumulations, in which the necessary elements of a valid petroleum system were identiﬁed. These include excellent or good potential for reservoirs and top seals as well as circumstantial evidence of regionally mature source rocks, possible seals, traps and hydrocarbon-migration pathways.

APA, Harvard, Vancouver, ISO, and other styles

44

Barbeau, David L. "Application of growth strata and detrital-zircon geochronology to stratigraphic architecture and kinematic history." Diss., The University of Arizona, 2003. http://hdl.handle.net/10150/280398.

Full text

Abstract:

Growth strata analysis and detrital-zircon geochronology are useful applications of stratigraphy to tectonic problems. Whereas both tools can contribute to kinematic analyses of supracrustal rock bodies, growth strata are also useful for analyzing the influence of tectonics on stratigraphic architecture. This study reports: (1) a conceptual model for growth strata development; (2) stratigraphic and kinematic analyses of growth strata architectures from growth structures in southeastern Utah, the Gulf of Mexico, and northeastern Spain; and (3) the detrital-zircon geochronology of the Salinian block of central coastal California. Kinematic sequence stratigraphy subdivides growth strata into kinematic sequences that are separated by kinematic sequence boundaries. Kinematic sequences can be further partitioned into kinematic domains based on the termination patterns of strata within a kinematic sequence. Salt-related fluvial growth strata from the Gulf of Mexico and southeastern Utah contain stratigraphic architectures that are unique to different kinematic domains. Offlap kinematic domains contain fluvial strata indicative of high slopes, low accommodation rates, and strong structural influence on paleocurrent direction. Onlap kinematic domains contain fluvial strata indicative of moderate slopes, high accommodation rates, and decreased structural influence on paleocurrent direction. The stratigraphic architecture of alluvial-fan thrust-belt growth strata in northeastern Spain does not display a marked correlation with kinematic domain, and is most easily interpreted using existing models for autocyclic alluvial-fan evolution. Detrital-zircon (U-Pb) geochronologic data from basement and cover rocks of Salinia suggest that Salinia originated along the southwestern margin of North America, likely in the vicinity of the Mojave Desert. The presence of Neoproterozoic and Late Archean detrital zircons in Salinian basement rocks also suggest that Salinian sediments were recycled from miogeoclinal sediments of the western margin of North America.

APA, Harvard, Vancouver, ISO, and other styles

45

Lindkvist, Maria. "A Phylogenetic Appraisal of Pachycormus bollensis: Implications for Pachycormiform Evolution." Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-177374.

Full text

Abstract:

The Pachycormiformes were a successful group of stem-teleosts. Although they persisted for more than 100 million years in the Mesozoic seas and occupied a significant space of the ecosystem, little is known about this most diverse group. One of the earliest pachycormiformes is the lower Jurassic Pachycormus bollensis. A reconstruction of the phylogeny with the early P. bollensis together with more derived and earlier studied species has yielded important information about the relationships within the group. Both a parsimony analysis and a Bayesian analysis were performed. Three exceptionally complete specimens of P. bollensis from the Holzmaden-locality were used for the study. The resulting trees strongly supported pachycormiform monophyly. Three major ecomorphological clades were returned from the analyses: the filter-feeders, hyper carnivores and a more generalist predator radiation that included P. bollensis. Despite, node support within the pachycormiformes are generally weak. The tooth-structure and the phylogenetic position of P. bollensis might indicate an intermediate grade between the filter-feeders and the hyper carnivores.
Pachycormiformer var en mycket framgångsrik ordning utav stam-teleoster. Trots att de överlevde i mer än 100 miljoner år i de Mesosoiska haven och erövrat ett flertal olika platser i ekosystemet, är denna mågfacetterade grupp som helhet tämligen okänd. Pachycormus bollensis från yngre jura är en av de tidigste arterna i denna grupp. En fylogenetiskt rekonstruktion av den tidiga P. bollensis tillsammans med yngre, mer utvecklade arter kan ge viktig information om släktskapen inom gruppen. En parsimonisk analys och en Bayesian analys utfördes. Tre exceptionellt bevarade exemplar av Pachycormus bollensis från Holzmaden användes i studien. Resultatet visar på ett stark monofyletiskt sammanband inom pachycormiformerna. Båda analyserna visade robusta resultat för tre övergripande grupper; filtrerare, karnivorer och en mer generell predator linje som inkluderar P. bollensis. Dock hade de interna släktskapen inom varje större grupp svagt stöd. Tand-stukturen tillsammans med den fylogenetiska placeringen av P. bollensis kan tyda på en intermediär grupp mellan filterarna och karnivorerna.

APA, Harvard, Vancouver, ISO, and other styles

46

Lanagan, Peter D. "Geologic history of the Cerberus Plains, Mars." Diss., The University of Arizona, 2004. http://hdl.handle.net/10150/290115.

Full text

Abstract:

This work examines the relative chronology of geologic units within the Cerberus Plains of Mars with an emphasis on lava flows emplaced after the last Marte Valles fluvial episode. High resolution images show the bulk of the Cerberus Plains is covered by platy-ridged and inflated lavas, which are interpreted as insulated sheet flows. Eastern Cerberus Plains lavas originate at Cerberus Fossae fissures and shields. Some flows extend for >2000 km through Marte Valles into Amazonis Planitia. Athabasca Valles are both incised into pristine lavas and embayed by pristine lavas, indicating that Athabascan fluvial events were contemporaneous with volcanic eruptions. Deposits of the Medusae Fossae Formation lie both over and under lavas, suggesting the deposition of the Medusae Fossae Formation was contemporaneous with volcanism. Statistics of small craters indicate lavas in the Western Cerberus Plains may be less than a million years old, but the model isochrons may be unreliable if the small crater population is dominated by secondary craters. Images showing no large craters with diameters >500 m superimposed on Western Cerberus Plains lavas indicate the same surface is younger than 49 Ma. High resolution Mars Orbiter Camera (MOC) images have revealed the existence of small cones in the Cerberus Plains, Marte Valles, and Amazonis Planitia. These cones are similar in both morphology and planar dimensions to the larger Icelandic rootless cones, which form due to explosive interactions between surficial lavas and near-surface groundwater. If martian cones form in the same manner as terrestrial rootless cones, then equatorial ground-ice or ground water must have been present near the surface in geologically recent times. Evidence for a shallow lake in the Western Cerberus Plains during the Late Amazonian is also presented. High-resolution images show features interpreted as flood-eroded scarps and fluvial spillways exiting the lake. Based on present-day topography, a lake would have covered an area of 8.4 x 10⁴ km², had an average depth of 12 m, and have contained a volume of 1.0 x 10³ km³ of water. Lake waters were likely primarily lost to the atmosphere through sublimation, although some quantity of water likely spilled into the Eastern Cerberus Plains or infiltrated into the shallow crust.

APA, Harvard, Vancouver, ISO, and other styles

47

Janal, Martin Joel. "Classification of the foraminifera : a case study in taxonomy and its history." Thesis, University of Cambridge, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.278154.

Full text

APA, Harvard, Vancouver, ISO, and other styles

48

Emblin, S. R. "The Reinfjord ultramafic complex, Seiland province : emplacement history and magma chamber model." Thesis, University of Bristol, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.355634.

Full text

APA, Harvard, Vancouver, ISO, and other styles

49

Wilson, Doyle Coley. "Post-middle Miocene Geologic History of the Tualatin Basin, Oregon with Hydrogeologic Implications." PDXScholar, 1997. https://pdxscholar.library.pdx.edu/open_access_etds/4711.

Full text

Abstract:

The geologic history and sedimentary till of the Tualatin Basin after Columbia River Basalt Group (CRBG) emplacement is assessed and related to groundwater characteristics. The 334 m deep HBD-1 core from the Hillsboro Airport, provides the primary information for sediment characterization and is supported by over 2400 well logs and cores, and four seismic lines. The sedimentary section above the 26 m thick paleosol on the CRBG in HBD-I is divided into two main groups: a 25 m thick section of Missoula flood sediments called the Willamette Silt overlies a 263 m thick finegrained sequence of fluvial Neogene sediments. Pollen, diatom and paleomagnetic data support dividing the Neogene sediments into a 230 m thick Pleistocene package and an underlying, 75 m thick Pliocene to upper Miocene unit. Heavy mineral and INAA chemical analyses indicate that the Neogene sediments were primarily derived from local highlands surrounding the Tualatin Valley. The structure of the top CRBG in the Tualatin Basin exhibits two provinces, a larger northern subbasin with few faults cutting the Neogene sediments above the CRBG and a smaller, more complexly faulted, subbasin south and east of the Beaverton Fault. Neogene sedimentation rates increased ten fold from the late Miocene-Pliocene to the Pleistocene, concomitant with increased basin subsidence. Comparison of Neogene basin evolution among Willamette Valley depositional centers reveals similarities among gravity and seismic reflection characters and subsidence timing between the Tualatin Basin and the northern Willamette Basin and out of phase with the Portland Basin. The Tualatin River CRBG nickpoint near the river's mouth has remained essentially unchanged since the Missoula floods filled the basin 12,700 years ago. This has kept the river from cutting back into the valley resulting in the low gradient evident today. Elevated orthophosphate levels in the upper 140 m of the Neogene sediment section indicate that the sediments are a natural source of phosphorus supplied to groundwater. Groundwater conditions in the lower Neogene sediments promote stabilization of phosphorus as vivianite. The unconfined Willamette Silt aquifer and the underlying confined Neogene aquifers are distinct, separate hydrogeologic units and usually yield less than 40 1pm.

APA, Harvard, Vancouver, ISO, and other styles

50

Sidamon-Eristoff, Constantine P. "The "Whys" of the Grand Cameo| A Holistic Approach to Understanding the Piece, its Origins and its Context." Thesis, Sotheby's Institute of Art - New York, 2019. http://pqdtopen.proquest.com/#viewpdf?dispub=13423363.

Full text

Abstract:

The Grand Cameo for France is the largest cameo surviving from antiquity. Scholars have debated who is portrayed on the stone and what its scene means for centuries, often, although not always, limiting their interpretations to this narrow area and typically only discussing other causes in passing. This pattern can and should be broken, allowing the stone to be what all objects truly are: windows to the lives that that objects have lived, just as all physical things are; evidence of an experience part of the world went though, whose meanings have and continue to be part of a wider network of object-meanings. The underlying purpose of this thesis is to use the Grand Cameo to prove this point. It does so by asking why the Grand Cameo came into being using Aristotle's four-part fragmented "Why" to widen this meaning broadly enough to expand the scope of what cause means from the vernacular use of the term to include material, formal, efficient and final causes. This allows for a sufficiently satisfactory exploration of many elements of the ancient world.

This thesis comprises an introduction, five chapters, and a conclusion. The first chapter discusses the material sardonyx itself, its possible origin points and how it would have been seen and used in its time in both the India and the west. It discusses the development of trade routes through the Indian ocean and Hellenistic and Egyptian ties to the east which were later taken over by Rome, as well as the Ptolemies, who they replaced. The second chapter discusses the relationship between Rome and Egypt, how their imagery and materials were usurped, and how this connects to the cameo, a medium that became Roman. Chapter three discusses Rome's absorption and reuse of Hellenistic kingdoms, their people and their culture to see how these influenced images of Roman Rulers in the transition from the Republic to the Julio-Claudians. The fourth chapter details the nature of Julio-Claudian power in Rome, the roles the family took over, and how they made themselves essential to the state, especially in how this relates to imagery from the Grand Cameo. Finally, the fifth chapter allows for the exploration of final cause by using a process of elimination based on living number of family members to establish a coherent narrative for the stone's scene, allowing an interpretation of message and intent. It seems most likely to be justifying the handing over of power to Emperor Claudius as intended by the heavens regardless of the plans of his relatives.

A roughly chronological understanding of this stone's role from being plucked from the ground to the imperial court is presented by assessing available material. The expansive nature of the question "Why?" allows for an explanation of the stone both broader and more satisfactory than the intentions of one emperor alone, however interesting. The Grand Cameo intersects with the highly international and interactive dynamics of the ancient world as well as specific elements therein which earlier interpretations do not allow for room to explore.

APA, Harvard, Vancouver, ISO, and other styles

Dissertations / Theses on the topic 'History of geology and palaeontology'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles