Sylvi Haldorsen

Norwegian University of Life Sciences (NMBU) · Department Environmental Sciences

Quaternary sand dunes and underlying Pliocene-Oligocene materials host the key groundwater resources that provide the only source of drinking water for a large proportion of Maputo district (Mozambique). This resource is at risk due to potential over exploitation, pollution and salinization. Few hydrogeochemical studies have been conducted in the r...

Sets of sandy beach ridges and intervening swales define shoreline sections of the shallow St Lucia wetland system within the iSimangaliso Wetland Park, World Heritage Site in northern KwaZulu-Natal province, South Africa. The sets comprise 3–10 beach ridges, the most prominent being 80–150 m wide and rising 0.5–2 m above the adjacent swales. The h...

Groundwater sources supply fresh drinking water to almost half of the World's population and are a main source of water for irrigation across world. Characterization of groundwater resources, surfacegroundwater interactions and their link to the global water cycle and modern global change are important themes in hydrogeological research, whereas li...

The domestication of the one-grained einkorn (Triticum monococcum) in the Near East is relatively well known. However, an independent two-grained einkorn-like domestication has been archaeobotanically detected and scarce information is available. Triticum urartu, a wild wheat, was not fully described until the 1970s because the phenology does not a...

St Lucia is the world's oldest protected estuary and Africa's largest estuarine system. It is also the centerpiece of South Africa's first UNESCO World Heritage Site, the iSimangaliso Wetland Park, and has been a Ramsar Wetland of International Importance since 1986. Knowledge of its biodiversity, geological origins, hydrology, hydrodynamics and th...

St Lucia is the world's oldest protected estuary and Africa's largest estuarine system. It is also the centerpiece of South Africa's first UNESCO World Heritage Site, the iSimangaliso Wetland Park, and has been a Ramsar Wetland of International Importance since 1986. Knowledge of its biodiversity, geological origins, hydrology, hydrodynamics and th...

Studies on the Earth’s hydrology in general thrive on abundant data, while data on certain groundwater systems are virtually absent as a result of their inaccessibility. This poses challenges for understanding and modeling such systems, yet modeling is often the only option to study them. When it comes to limited data availability, a simple model m...

The configuration of coastal groundwater systems in southeast Africa was strongly controlled by the Holocene sea-level changes, with an Early Holocene transgression ∼15 m (10,000–5000 cal BP), and two assumed high-stand events in the Middle and Late Holocene with levels higher than the present. The fluctuation of the salt–fresh groundwater interfac...

Polar areas experience a temperature increase due to global warming, with decrease of permafrost thickness. Permafrost degradation may give dramatic changes in the interaction between groundwater and surface water. In areas where permafrost is thick and continuous no changes in the subpermafrost groundwater flow- pattern is reported. However, here...

The domestication of the Neolithic founder crops of the Near East has recently been a topic of debate particularly with respect to how rapidly the domestication of these crops occurred. One school of thought maintains that these processes lasted several thousand years (‘protracted model’ with ‘gathering’, ‘cultivation’ and ‘domestication’ as three...

Over the past few years groundwater has been recognized as an important contributor of freshwater to Lake St Lucia, South Africa during periods of prolonged drought. This has led to a management strategy aiming at increasing the groundwater recharge and minimizing groundwater use through active manipulation of the vegetation. For the Eastern Shores...

Deep subpermafrost aquifers are highly climate-dependent, with the permafrost as an aquitard preventing groundwater recharge and discharge. A study from the high-arctic island of Spitsbergen, Svalbard, shows that during a glacial to interglacial phase, both the permafrost and the glacier regime will respond to climatic changes, and a glacier-fed gr...

The results from a Nordic research project on Quaternary geology, entitled the Nordkalott project, were presented at a symposium in northern Sweden in 1987. Organic deposits and tills in northern Fennoscandia are interpreted as belonging to the Eemian as well as to interstadials and stades of the Weichselian. Retreat of the ice front under cold cli...

To reassess domestication events in the Near East, accessions of Triticum urartu from a well-described sampling were combined with a representative sample covering the Karacadağ Einkorn wheat domestication. The observed DNA separation between the two wheat species accounts for the main differentiation, but geographic variation within T. urartu is e...

A subglacial till formed from a sandstone bedrock has a variable grain-size distribution which reflects its variable genesis. Glacial comminution processes were simulated by artificial mill experiments with fragments of the sandstone bedrock. Pure crushing caused disintegration along mineral boundaries into separate minerals, most mineral grains re...

A complete interglacial cycle, named the Fjøsangerian and correlated with the Eemian by means of its pollen stratigraphy, is found in marine sediments just above the present day sea level outside Bergen, western Norway. At the base of the section there are two basal tills of assumed Saalian (sensu lato) age in which the mineralogy and geochemistry...

Deposition of till by melt-out was described as early as a hundred years ago, and today the criteria which provide evidence to support an interpretation of melt-out till are available. The most important criteria are (P1) the presence of unlithified, sorted and stratified sediments within or interstratified with the till(s). (P2) the presence of a...

The clay mineral composition of a number of Saalian till samples from The Netherlands shows a large variation in smectite and illite abundances. The samples were selected according to their source area, as inferred from coarse erratic components. Specimens containing primarily rock fragments indicative of East and East-Central Baltic areas are asso...

The ecology of the St Lucia estuary in South Africa is of unique international importance. During droughts the estuary experiences high salinities, with values above that of seawater. Ion-poor groundwater flowing into the estuary from prominent sand aquifers along its eastern shoreline forms low-salinity habitats for salt-sensitive biota. During dr...

A study of baseline groundwater chemistry has been carried out in the pristine areas around Eastern Shores, Lake St Lucia, North-eastern South Africa. The study aims to provide a quality baseline against which anthropogenic (urban) impacts elsewhere may be evaluated. In general, groundwater in the Eastern Shores region is of low conductivity, and a...

Four primary habitats have been identified in the St Lucia estuarine system, each having a suite of characteristic vegetation types. These can be described as follows: (1) open water; (2) intertidal shoreline; (3) 'dry' shoreline and island (i.e. those habitats without any freshwater source other than rainfall); and (4) groundwater-dependent shorel...

St Lucia, is a large coastal lagoon, which is very sensitive to changes in water level, volume and quantities of inflowing freshwater. It is therefore sensitive to the effects of global change that alter sea levels and rainfall. Earlier studies have shown that, during the Eemian, St Lucia was a marine environment. At that time global sea level was...

Estuaries along the south east coast of Africa are characterised by extreme hydrological conditions that have a profound influence on their ecology. Large fluctuations in water quality (particularly salinity concentrations) and water quantity (principally water levels) in many of the major estuaries impact significantly on the biota of these dynami...

Lake Tvillingvatne t is the water supply to the arctic research settlement Ny-Ålesund in Svalbard. In the period 1920–1930 it was observed that the lake received groundwater from a sandstone-aquifer underlying the lake. Recent water balance studies indicate that there is no longer any groundwater  ow of that type into the lake. This change can be...

Trollkjeldene, Jotunkjeldene and Gygrekjelda are groups of low temperature (<25.6°C) thermal springs, with major travertine mound and terrace development, on the prominent Breibogen-Bockfjorden fault in a recently volcanically active area of northern Svalbard. The likely Quaternary history of the springs supports current models of recharge beneath...

It generally is assumed that the Early Permian Gondwana deglaciation in South Africa started with a collapse of the marine ice-sheet. The northeast part of the Karoo Basin became ice-free as a result of this collapse. The deglaciation here probably took place under temperate glacial conditions. Three glacial phases have been identified. Phase 1: th...

It has recently been possible to trace groundwater and contaminants flow paths by using synthetic DNA molecules as tracers. The DNA tracers injected in groundwater can be as distinctive and traceable as a person’s fingerprint. Alphanumeric information like names, dates, batch numbers, can be defined into the DNA sequence. This novel tracing te...

Waters from the Trollkjeldene (Troll springs) and Jotunkjeldene (Jotun springs) thermal springs on northern Svalbard have been analysed by ICP-AES, ICP-MS and IC techniques for a wide range of major and trace elements. Although it is plausible that the thermal waters originate from a deep reservoir in siliceous rocks, it appears that a significant...

Arctic groundwater systems are climatically controlled. On Svalbard, the permafrost forms a 100 to 400-m thick and fairly continuous aquitard, and the groundwater recharge is mainly restricted to the temperate basal zones of the glaciers. The glaciers in this permafrost region are mainly of a multithermal type, with permafrost conditions under the...

In order to investigate the usefulness of unique synthetic DNA tracers in groundwater, a field experiment was conducted in Norway. DNA tracers and a sodium-chloride tracer were injected into an aquifer. The transport of DNA molecules was interpreted by comparing with the plume of chloride ions under forced-gradient steady-state flow conditions. Spa...

Arctic groundwater systems are climatically controlled. On Svalbard, the permafrost forms a 100-400 m thick and fairly continuous aquitard, and groundwater recharge is mainly restricted to the temperate basal zones of the glaciers. The climate changed quite quickly and became milder when the Little Ice Age ended at the end of the last century. Stud...

Svalbard is a high arctic archipelago where the permafrost thickness is 150-450 m and almost continuous in ice-free areas. The model work was carried out in Ny-Ålesund, where the subpermafrost aquifers are recharged by water from the bottom of the Vestre Lovénbreen glacier. One main discharge spring is found at the entrance of an old coal mine. The...

The Troll and Jotun thermal springs of northern Svalbard, with temperatures of up to 25.6°C, are derived from a major fault forming the junction between Devonian sandstones and Proterozoic marbles, mica schists and gneisses. The Troll waters are dominated by Na–HCO3 compositions and the Jotun waters by Na–Cl compositions. The pristine thermal water...

Svalbard is a high arctic archipelago where the permafrost thickness is 150-450 m and almost continuous in ice-free areas. The model work was carried out in Ny-Alesund, where the subpermafrost aquifers are recharged by water from the bottom of the Vestre Lovenbreen glacier. One main discharge spring is found at the entrance of an old coal mine. The...

In July 1996, a team of researchers visited the "Troll" and "Jotun" springs of northern Svalbard to carry out mapping and sampling activities. The main conclusions of the hydrochemical survey will be reported in scientific articles in the Journals "Geothermics" and "NGU Bulletin". This report serves to document the data used in these articles and...

In July 1996, a team of researchers visited the "Troll" and "Jotun" springs of northern Svalbard to carry out mapping and sampling activities. The main conclusions of the hydrochemical survey will be reported in scientific articles in the journals "Geothermics" and "NGU Bulletin". This report serves to document the data used in these articles and...

Published in Norges geologiske Undersøkelse Bulletin 433, 60-61

Subpermafrost groundwater aquifers are found in Ny-Alesund, western Svalbard. Recharge of groundwater takes place along the base of the nearby glaciers, and groundwater flows in open bedrock fracture systems and porous sedimentary rocks. A subpermafrost sandstone with a primary porosity of more than 10% makes up a pore aquifer with a considerable s...

Hydrogeological properties of tills are highly dependent upon factors as grain-size distribution, compaction, orientation of particles, presence of fractures and occurrence of sorted sediments. These factors are again dependent upon the till forming processes. Lodgement tills formed under active, temperate sliding glaciers are usually compact, rath...

(1) Modeling of the water balance of the unsaturated zone and (2) calculating the Darcian flux have been applied for determining groundwater recharge. Modelling was based on field and laboratory studies, including soil moisture measurements, infiltration experiments, textural analysis and retention measurements. Method (1) is not particularly sensi...

The southern marginal zone of the Saalian till plain in the northern Netherlands is marked by a series of low glaciotectonic hills that are characterised by exceptionally thick till occurrences and a high degree of compositional variability within this till. Structural and compositional anslyses of a construction site near Steenwijk and of some rel...

There is an increasing till thickness from the Oslofjord area towards the north. In the southernmost zone, close to the fjord, there are continuous and marked ice marginal ridges with a high content of diamicton. Between the ridges there is a lack of till. Basal erosion behind the ice margin and deposition of material in frontal zones explain the p...

Chemical profiles of water in the vadose zone and in the upper part of the groundwater from a water-table sand-silt aquifer at Haslemoen, South Norway, have been studied. Filter tips attached to steel pipes (BAT monitoring system) have been installed to different depths at two localities. The system makes it possible to measure pore pressures and h...

Along Glama in Solor the silty surface soil is named 'koppjord' and has been of great agricultural importance for many generations. At Haslemoen measurements of the saturated hydraulic conductivity in the field and in laboratory gave values between 4.10-6m/s and 5.10-5m/s, the highest values obtained by field tests. Compared with other Norwegian Qu...

In Astadalen, SE Norway, the size distribution of minerals in basal till is dependent on the processes of glacial grinding and on the influence of meltwater. An experimental crushing gave a size distribution of minerals corresponding to that in the source rocks and insignificant comminution of separate mineral grains. An experimental abrasion resul...

This study was designed to discover whether comminution during glacial transport and deposition may result in mineralogical fractionation, and whether, in combination with other glacigenic processes, it may produce glacial sediments with a bulk petrographical composition differing significantly from that of the source rocks. -K.Clayton

Ice movements in Astadalen originated from the north and later from the northwest. Most of the area is covered by a 1-5 m thick till which does not create independent landforms. In the mountainous areas, this till is local and coarse-grained and interpreted as a subglacial melt-out till. Along the western valley side and western upland area, the ti...