The dynamic interaction between different water sources plays a key role in the structure and functioning of Arctic stream systems. Ice melt, snowmelt, groundwater and rainfall mix to produce a diverse range of physicochemical conditions. The heterogeneous habitat matrix created is home to a variety of cold stenothermic species. Recent trends in earth surface temperatures associated with global warming have co-in sided with a reduction in global glacier mass balance and a hastening in the onset of spring thaw. This field based study investigated the physicochemical habitat diversity within a glacierized Arctic catchment, Kårsavagge in Northern Sweden. Hydrological, meteorological and physicochemical data spanning 2007 to 2010 were collected with intensive collection during the summer melt seasons of 2008 and 2009. In conjunction with these data, macroinvertebrate and fish sampling was carried out during both of the intensive summer monitoring periods. The key focus of the sampling regime was to compare lateral and longitudinal habitat variability, investigate the extent to which this was linked to dynamic water source interactions by modeling contributions from identified sources and assess the impact of this physicochemical habitat template on the macroinvertebrate and fish communities in the light of predicted climate change. The key findings discussed within are (1) Lateral habitat and biological diversity was equivalent to that observed longitudinally. (2) The ARISE framework used for modeling different water source contributions is applicable to an Arctic scenario, however its utility decreases with increasing catchment size. (3) The key habitat variables structuring macroinvertebrate and fish distribution were concerned with mediating/ mitigating the extent of the glacial signal. A conceptual model is presented that illustrates the potential impact of loss of this glacial signal on local biodiversity.

The research described in this thesis primarily investigates the scope of IP (induced polarisation) as a method of determining the permeabilities of Bunter sandstones in situ. Although a limited amount of preliminary fieldwork has been completed, the project has been largely confined to the laboratory, directed toward identification of the petrophysical factors involved, rather than determination of aquifer geometry. In contrast: to all of the previous studies, the conclusions are supported by a large number of measurements. IP has been measured in the time domain exclusively. Compared to the frequency domain method this offers the advantages of a wider scope of information from which a suitable measure of chargeability may be selected, together with the facility to monitor the potential decay for spurious results. The variation of IP with permeability was investigated for a large number of sandstones with suitable pore water control, and because of the diversity of the results a representative selection of the samples was then subjected to further measurements of IP over a range of pore water salinities. All these data have been described by empirical expressions which relate IP, permeability and matrix conductivity, and some geological implications of these results have been considered. Preliminary fieldwork has been done in the Fylde to find out whether an empirical relationship determined in the laboratory can be used to evaluate field permeabilities directly. The problems involved have been considered and further work in this direction is suggested.

Στα πλαίσια αυτής της πτυχιακής εργασίας μελετώνται οι υδρογεωλογικές συνθήκες της βόρειας πλευράς της λίμνης Τριχωνίδας και ειδικότερα ο προσχωματικός υδροφόρος στην περιοχή μελέτης μας. Το υπόβαθρο της περιοχής δομείται από αποτελείται από σχηματισμούς φλύσχη (σχιστόλιθοι, ψαμμίτες με κροκαλοπαγή και μάργες). Το κύριο αντικείμενο αυτής της εργασίας είναι να καθορίσει τις παραμέτρους του υδρολογικού ισοζυγίου χρησιμοποιώντας υδρο-μετεωρολογικά στοιχεία και την τεχνολογία γεωγραφικών συστημάτων GIS και να διερευνηθούν οι συνθήκες τροφοδοσίας του υδροφόρου ορίζοντα καθώς και οι αλληλεπιδράσεις του υδροφόρου με την λίμνη Τριχωνίδα . / In the frame of this final work the hydrogeological conditions that prevail at the north side of lake Trichonida and especially the aquifer in our search ground. The geological background of the region is structured by flysch. The main objective of this work is to determine the parameters of hydrological balance using hydrometeorological data and geographic information systems (GIS) technology and determine the supply conditions of the aquifer as well as the interaction between the aquifer and the lake Trichonis.

A descriptive sediment movement model has been created for an area of the nearshore zone near Gibraltar Point, Lincolnshire on the basis of evidence from studies of sediments, sandbank and channel morphology, bedforms, tidal currents and sediment tracer experiments. The area is subject to linear tidal currents which have created a system of tidal current ridges, tidal channels and an ebb-tidal delta. Sediment movement associated with these sandbanks and channels was found to have a net northerly drift related to an ebb tidal residual in the Boston Deep, the largest channel in the area. Sediment circulation around the sandbank system was considered to be essentially closed with a large sediment storage element represented by the sandbanks. An area of the foreshore was identified as a possible location for movement of sediment from the nearshore zone to the foreshore zone. Six Woodhead seabed drifter experiments were conducted to assess the validity of the sediment movement model. The net northerly drift of the sediment within the sandbank system was confirmed and was found to extend as far north as Ingoldmells Point. Movement of sediment from the nearshore zone to the foreshore zone was confirmed at the location suggested in the sediment movement model and was also predicted at Ingoldmells Point. The time of stranding of seabed drifters was found to coincide with periods of winds blowing offshore and from the north-east and with, periods of increasing tidal current velocity as the lunar tidal cycle approaches spring tide conditions. Movement of sediment from the nearshore zone to the foreshore zone may also occur under these environmental conditions. A study of the historical development of the sandbanks suggested an overall decrease in the size of tidal current ridges since 1871 which may be related to a decrease in the amount of sediment available for the maintenance of the sandbanks. A ness south of the Skegness Middle sandbank was interpreted as a morphological expression of foreshore adjustment to the migration of sediment from the nearshore zone to the foreshore zone at this location.

Typescript / Bibliography: leaves 145-150 / vii, 150 leaves : ill ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Applied Mathematics, 1988

Η περιοχή μελέτης βρίσκεται στο ΒΑ Αιγαίο και είναι το όγδοο μεγαλύτερο νησί της Ελλάδας με έκταση 476 τετραγωνικά χιλιόμετρα και μήκος ακτών 260 χιλιομέτρων. Η «Λημνία γη» είναι ένα προϊόν που στην αρχαιότητα ήταν γνωστό για τις θεραπευτικές του ιδιότητες. Το προϊόν αυτό που στήριξε την οικονομία του νησιού για αιώνες ήταν χώμα που εξορυσσόταν από συγκεκριμένο σημείο και θεράπευε μια σειρά ασθενειών. Η τοποθεσία από όπου εξορυσσόταν η «Λημνία γη» βρίσκεται περίπου στο κέντρο του νησιού ένα χιλιόμετρο περίπου από τον οικισμό Κότσινα και το ακριβές σημείο του σκάμματος εντοπίζεται σε επίπεδη έκταση κοντά στην κορυφή του λόφου Μόσυχλον. Η γεωλογική και γεωτεκτονική ανάλυση της ευρύτερης περιοχής μελέτης Ν. Λήμνου ήταν δυσκολο λόγω του ότι βρίσκεται από γεωγραφικής άποψης σε μια θέση η όποια δεν ανήκει σε καμία γεωτεκτονική ζώνη. Στην Λήμνο υπήρξαν 2 περίοδοι ηφαιστειακής δραστηριότητας. Η παλαιότερη αντιπρόσωποι κυρίως από λαβες της Βορειοδυτικής πλευράς του νησιού και τα περικλύστηκα της περιοχής Βάρους – Ρεπανίδι (περιοχή μελέτης) και η νεώτερη ηφαιστειακή δραστηριότητα κυρίως από θόλους της περιοχής μεταξύ Μύρινας και Κοντια (ΝΔ πλευρά). Οι δυο κύριες φάσεις ηφαιστειότητας τις συναντάμε και σε μικρές εμφανίσεις στην κοιλάδα της Αστικής (Καρπασι) όπου ανάμεσα στους τοφφους και στα ηφαιστειακά λατυποπαγη έχουμε μικρά στρώματα τοφφιτων που δείχνουν σαφή ιζηματογενή χαρακτήρα. Τα αποτελέσματα των εργαστηριακών αναλύσεων μας έδειξαν ότι τα νερά της περιοχής μελέτης είναι Γαιοαλκαλικά νερά με υψηλό ποσοστό αλκαλιών - (Na–CI–SO4, Na–CI Ca-Na–CI- HCO3). Αλκαλικά νερά – χλωριοθειικά (Na–CI-HCO3 , Na–Mg–Ca–CI–HCO3, Na–CI–SO4). Η πλειοψηφία των δειγμάτων έχουν υδραιμικό τύπο Na– CI – HCO3. Σε όλα τα δείγματα μας έχουμε την παρουσία Na και CI αυτό μπορούμε να πούμε ότι προέρχεται ένα μέρος του από την ανάμιξη με το θαλασσινό νερό. To SO4 το όποιο είναι σε υψηλές συγκέντρωσης σε κάποια δείγματα μας οφείλετε πιθανά στην διείσδυση του θαλασσινού νερού. Τα θειικά ιόντα προέρχονται συνήθως από την διάλυση της γύψου και του ανίδρωτη. Προέρχονται επίσης από την οξείδωση τον πυριτών που εμφανίζονται σε αργιλικά και αλλά πετρώματα. / --

Σκοπός της εργασίας αυτής είναι η προσέγγιση και μελέτη των υδρογεωλογικών συνθηκών που επικρατούν στην περιοχή της Εύβοιας και συγκεκριμένα στην λεκάνη του Μανικιάτη ποταμού. Ο ποταμός διασχίζει το σημείο επαφής δύο γεωτεκτονικών ζωνών, της Πελαγονικής και της Αττικοκυκλαδικής αποτελώντας ένα φυσικό δίαυλο ανάμεσα στις γεωμορφολογικά και γεωλογικά ετερόκλητες Βόρεια και Νότια Εύβοια. Στο πλαίσιο της παρούσας εργασίας πραγματοποιήθηκαν μετρήσεις στάθμης των πηγαδιών που βρίσκονται στη λεκάνη του ποταμού, δειγματοληψίες και υδροχημικές αναλύσεις και κατασκευάστηκαν αναλυτικοί χάρτες και διαγράμματα για την ανάλυση των υδρογεωλογικών συνθηκών. Επιπλέον, συγκεντρώθηκαν παλαιότερες μελέτες που αφορούν γεωλογικά στοιχεία της ευρύτερης περιοχής, καθώς και κλιματολογικά δεδομένα από αρμόδιες υπηρεσίες. / The purpose of this essay is the approach and study of the hydrogeological conditions of the area of Evia and specially of hydrological basin of the river Manikiatis. Manikiatis river runs over two separate geological zones, the Pelagonian Plate and the Attico Cycladic Massif, as a natural border between the geologically and geomorphologically different South and North Evia.For the purpose of this essay were used measurements of the groundwater levels, relevant research and data for the study area, meteorologial data from national agencies, samples for hydrochemical analysis in the laboratory of the Department of Geology and map construction with Geoproccessing and map digitizing programs.

The aims of this thesis are to refine the tephrochronology of the Öræfi district, SE Iceland and assess the Holocene glacier fluctuations of the Öræfajökull ice cap. The pattern and timing of glacier fluctuations are determined using glacial geomorphology and tephrochronology, and the implications for palaeoclimate are assessed. Iceland is important to the study of global and regional climatic change because it is located close to both the marine and atmospheric Polar Fronts widely regarded as the key factors in the climate of the North Atlantic region. Six outlet glaciers were studied: Svinafellsjökull, Virkisjökull, Kotárjökull and Kviárjökull originating from the Öræfajökull ice cap and Skaftafellsjökull and Morsárjökull originating from the Vatnajökull ice cap. A long history of glacier fluctuations were found with a similar temporal pattern of glacier oscillation between the outlets of Vatnajökull and Öræfajökull. A maximum of eight advances have been identified. The oldest advance is inferred to date from the maximum of the last Glaciation ca. 18000 yrs BP. The first advance in the Holocene occurred ca. 9700 BP during a still-stand of the last Termination. The onset of the Neoglaciation occurred between 6000 BP and 4600 BP with an expansion of all of the studied glaciers. Subsequent smaller advances have been dated to ca. 3200 BP, ca. 1800 BP, ca. 700 BP, ca. 200 BP and ca. 80 BP. The most significant movement of the Polar front during the Holocene is likely to have occurred around 5000 BP, and, as a consequence, an estimated temperature cooling of ca. 2.5°C took place in Iceland, perhaps the greatest cooling since the last Termination. Within the broad pattern of change, glaciers in the study area show variability which represents local precipitation patterns, contrasting topography and change in glacier process. In this thesis a total of 22 silicic tephra layers are identified from over 90 profiles in the study area. The majority of these layers are dated to the latter part of the Holocene. Three silicic tephras were deposited during historical time (post 900 AD) namely, Vö ca. 900AD,HI104 and Ö1362. The Vö ca. 900 AD and the H1104 tephras are located for the first time. Specific prehistoric (pre 900 AD) tephras identified include Hekla-Ö, Hekla-4 and Hekla-S. The tephrochronology of the Öræfi district is also used to assess the eruption history of the Öræfajökull stratovolcano during the Holocene. Prehistoric eruptions are dated to ca. 9200 BP, ca. 6500 BP(?), ca. 4700 BP, ca. 2800 BP and ca. 1500 BP. Jökulhlaups accompanied the eruptions of 1727 AD, 1362 AD and ca. 1500 BP and are likely to have followed older eruptions of the volcano. A strong relationship occurs between volcanic activity of the Öræfajökull stratovolcano and the pattern of glacier fluctuations. This is explained as a response to isostatic crustal adjustment during ice cap growth and decay, and indicates a general relationship between volcanic activity and climate change.

The Laurentine Shore is the Imperial Roman palaeo-shoreline preserved up to 1km inland of the southern, distal edge of the Tiber Delta coastline of Lazio, western Central Italy. The progradation of the delta is recorded on the site as a series of shore-parallel relict dune ridges. High-status villas developed along the roman period coastline, with a service village (Vicus Augustanus), and other infrastructure such as roads, aqueduct, piscinae and several baths (thermae), these structures have been examined using a multi-scale geoarchaeological approach. A sea level reconstruction based on multi-proxy palaeo-environmental analysis of a silt/peat sedimentary transition from the base of a Roman piscina suggests that the sea level at ca. 2400 ± 40 BP was around 1.25 ± 0.2 m below modern sea level. This analysis provides further context for assessing the development of the site during the late Holocene in relation to the progradation of the Tiber delta and for the important Imperial Roman period occupation of the Laurentine Shore and other important sites such as Portus and Ostia Antica in the central part of the Tiber delta. At several key periods in the late Holocene, the palaeo-shoreline has been reconstructed using a geochronological framework of optical luminescence dates and geomorphological survey of the Tiber Delta dune ridge record. In particular, during the Imperial Roman period, ca. 2000 BP) it has been shown that the Laurentine Shore was settled during a period of significant Tiber delta shoreline progradation. Two-major building phases at the Vicus Augustanus occur within this progradation phase. By the abandonment of the site in the 5th century AD, the shoreline was around 70 m seaward of the shoreline during the 1st building phase of the Vicus. This rate of shoreline change could be noticeable by the population over decadal timescales and may have driven the alteration of coastal building and property plots during the 500 year lifetime of the settlement. A combined methodology incorporating sedimentology, geochemistry and petrological analysis of diagenetically altered sediments found that early vadose diagenesis may have a deleterious effect upon luminescence dating dosimetry, inducing age underestimation, especially of reddened dune sands. Petrological analysis has also shown that a lack of anomalous fading in luminescence behaviour observed in K-feldspars may be due to a lack of complex microstructure in the mineral grains driven by the metamorphic, Alpine origin of these minerals. An assessment of the geoarchaeological approach used in this thesis shows that a scale-driven context provides a useful structure for examining the various processes and factors affecting the geomorphological and sedimentological records improving confidence in the examination of the archaeological record.

This thesis presents the results of contemporary limnological and palaeolimnological investigations of a series of crater lakes in order to reconstruct the palaeoenvironmental history of western Uganda, East Africa. The research examines questions of spatial and temporal heterogeneity of climate changes in the context of growing human impacts on the landscape over the last millennium. Sediment records from two lakes, Nyamogusingiri and Kyasanduka within the Queen Elizabeth National Park (QENP) were investigated to look at the long term records of climate and environmental change (spanning the last c. 1000 years). Five shorter cores across a land-use gradient were retrieved to assess the impact of human activity on the palaeoenvironmental record over the last ~150 years. High-resolution (sub-decadal), multiproxy analyses of lake sediment cores based on diatoms, bulk geochemistry (C/N and δ13C) and sedimentary variables (loss-on-ignition, magnetic properties and physical properties) provide independent lines of evidence that allow the reconstruction of past climate and environmental changes. This multiproxy approach provides a powerful means to reconstruct past environments, whilst the multi-lake approach assists in the identification and separation of local (e.g. catchment-scale modifications and groundwater influences) and regional effects (e.g. climatic changes). The results of a modern limnological survey of 24 lakes were used in conjunction with diatom surface sediment samples (and corresponding water chemistry) from 64 lakes across a natural conductivity gradient in western Uganda (reflecting a regional climatic gradient of effective moisture) to explore factors controlling diatom distribution. The relationships between water chemistry and diatom distributions were explored using canonical correspondence analysis (CCA) and partial CCA. Variance partitioning indicated that conductivity accounted for a significant and independent portion of this variation. A transfer function was developed for conductivity (r2jack = 0.74). Prediction errors, estimated using jack-knifing, are low for the conductivity model (0.256 log units). The final model was applied to the core sediment data.This study highlights the potential for diatom-based quantitative palaeoenvironmental reconstructions from the crater lakes in western Uganda. Sedimentary archives from the Ugandan crater lakes can provide high-resolution, annual to sub-decadal records of environmental change. Whilst all of the lakes studied here demonstrate an individualistic response to external (e.g. climatic) drivers, the broad patterns observed in Uganda and across East Africa suggest that the crater lakes are indeed sensitive to climatic perturbations such as a dry Mediaeval Warm Period (MWP; AD 1000-1200) and a relatively drier climate during the main phase of the Little Ice Age (LIA; c. AD 1500-1800); though lake levels in western Uganda do fluctuate, with a high stand c. AD 1575-1600). The general trends support the hypothesis of an east to west (wet to dry) gradient across East Africa during the LIA, however, the relationship breaks down and is more complex towards the end of the LIA (c. AD 1700-1750) when the inferred changes in lake levels at Nyamogusingiri and Kyasanduka are synchronous with changes observed at Lakes Naivasha (Kenya) and Victoria and diverge from local lake level records (from Edward, Kasenda and Wandakara). Significant changes in the lake ecosystems have occurred over the last 50-75 years, with major shifts in diatom assemblages to benthic-dominated systems and an inferred increase in nutrient levels. These changes are coincident with large sediment influx to the lakes, perhaps as a result of increasing human activity within many of the lake catchments.