Randaberg sentrum øst, plan 2011004: Jordbrukspor i gammel utmark : Harastad, gnr 49., bnr. 846, 847, Randaberg kommune, Rogaland

Oppdragsgiver: Randaberg kommuneArkeologisk museum gjennomførte undersøkelsen av lokalitet id 161040 i løpet av 10 uker om sommeren 2015. Hele lokalitetsflaten ble avdekket ved hjelp av gravemaskin, strukturene som viste seg i plan ble renset frem og undersøkt ved håndgraving. Undersøkelsen kunne påvise spor etter jordbruksaktiviteter og sporadiske opphold av menneskene siden bronsealderen. I området kunne rester av en rydningsrøys og en godt bevart stakketuft bli dokumentert. Det ble ikke funnet spor etter bosetning eller graver. På grunn av den sparsommelige funntilfanget ble undersøkelsen avsluttet tidligere enn planlagt. Det ble foretatt radiologisk datering av trekull fra 5 forskjellige strukturer. Noe overaskende viste 4 dateringer bronsealder og en datering yngre steinalder. Dette var eldre enn forventet. Jordbruk og sporadisk opphold i undersøkelsesområdet begynte etter disse dateringer allerede 3000 – 4000 år før nå. Sannsynligvis var undersøkelsesområdet en perifert del av en sentral gård i jernalderen, muligvis allerede i bronsealderen. Undersøkelsesresultatene viser til en utnytting av utmarksressurser

Engineering properties and microstructure of a sustainable roof tile manufactured with waste rice husk ash and ceramic sludge addition

Clay replacement with waste rice husk ash (RHA) and ceramic sludge (CS), helps to reduce the consumption of natural clay and solves the ecological issues created by waste disposal. In this study, properties of waste RHA and CS added fired clay tile were investigated, focusing on structural, durability, thermal performance as well as the water quality of the harvested run-off from fired clay roof tiles manufactured in an industrial scale plant. Tiles were cast by clay replacement with waste RHA and CS in four mixtures: 10 %RHA and 0 % CS, 10 % RHA and 10 % CS, 10 % RHA and 15 % CS, and 10 % RHA and 20 % CS (by weight). For 10 %RHA and 10 %CS tiles, dry mass was reduced by 4.9 %, compared with conventional roof tiles, promising a light weight roof tile. Roof tiles with 10 % RHA and 10 %CS showed a transverse breaking load of 1519 N, whereas that of 20 %CS tiles showed 1427 N, indicating that a further 6.5 % strength improvement can be achieved with clay replacement with a combination of two waste materials. Clay replacement with 10 % RHA and 10 % CS resulted in water absorption of 15.25 %. When increasing the clay replacement with combined waste from 10% (10 %RHA and 0%CS) to 30 % (10%RHA and 20 %CS), weight gain due to acid and alkaline attacks reduced from 3.5% to 3.0%, and from 2.2 % to 1.6 %, respectively, indicating enhanced durability performance by incorporating combined waste. High porosity, also confirmed by SEM, contributed to enhanced thermal performance: tile with 10 % RHA and 10 % CS achieved 4.4 °C temperature reduction, compared to the conventional tile. pH value and total solid concentration of run-off water were in the range of recommended values of water for agricultural purposes, ensuring that the collected run-off can be utilized as an alternative water source for potable activities.publishedVersio

Jarosite-Rich Mineral Crust on Coastal Cliffs in Central Norway: Microstructural and Geochemical Investigations

The study of jarosite produced under diverse conditions is essential to gain insight into its diverse formation mechanisms on earth. Such investigations can even pave ways to better understanding of the genesis of jarosite discovered in extra-terrestrial bodies such as Mars. Jarosite samples from two costal locations in central Norway are investigated through the application of multiple analytical techniques. The jarosite-rich encrustations on seaward cliff walls were studied with a focus on the characterization of their micromorphology and geochemistry. Light and electron microscopic analyses revealed distinct laminations and microlaminations in the samples. These layered laminations likely imply the existence of favorable periods in a cyclic manner for mineralization/biomineralization of jarosite in tandem with gypsum formation and dissolution. The pH level measured is not low similar to that usually described as conducive for jarosite formations. Different viable jarosite formation mechanisms are explored. Though some indicators are implied from microstructural and compositional analyses, further investigations are required for establishing the biogenic nature of the mechanism involved. Signs of the possible formation of jarosite in the Mid-Pleistocene Transition, 1.1–1.3 million years B.P., are acquired from Ar39/Ar40 geochronological determinations. Useful paleoenvironmental and paleobiological information could be found preserved in the microstructures of such jarosite formations

Synthesis and characterization of fly ash and slag based geopolymer concrete

This paper presents the formulation and characterization of composite fly ash and slag based geopolymer concrete. Potassium hydroxide (KOH) and potassium silicate (K2SiO3) liquid alkaline activators were used in the preparation of the geopolymer concrete. The mechanical response of the best recipe was investigated through compressive, tensile and flexural strength tests after 3, 7 and 28 days of curing. One batch was tested for compressive strength after 16 and 32 weeks of curing. The microstructure of the concretes was characterized using scanning electron microscopy (SEM). The testing results are compared with a reference ordinary portland cement-based concrete. After 28 days of curing, test results showed that the geopolymer concretes can approach the compressive strength of the reference ordinary concrete. Moreover, the tensile strength and flexural strength attained reached up to 68% and 80% of the reference cement, respectively. The results indicated the potential application of geopolymer that can satisfy the standard strength requirement. After longer time of curing, 32 weeks, some of the geopolymer preparations exhibited 111% compressive strength, compared to the ordinary cement reference.publishedVersio

Multi-analytical investigation into painting materials and techniques: the wall paintings of Abuna Yemata Guh church

Abuna Yemata Guh is one of the nine Saints who are traditionally claimed to have come to Northern Ethiopia in the beginning of the sixth century and established monasteries in the Tigray region. The church, named after him, is hewn out of the side of one of the highest sandstone spires in the Gheralta area. Though the local tradition claims earlier dates, the paintings in the church are suggested to belong to the second half of the fifteenth century on the basis of their theme, style and iconography. We report here the investigation into the materials and techniques of the paintings using diverse complementary analytical techniques: Polarized light microscopy (PLM), portable X-ray fluorescence spectrometer (pXRF), scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM–EDS), synchrotron-based X-ray diffraction (SR-XRD), pyrolysis gas chromatography-mass spectrometry (Py-GC/MS), micro-Raman spectroscopy (MRS) and micro-Fourier transform infrared spectroscopy (micro-FTIR). Earth materials based on hematite, goethite and terra verte were the main findings, but cinnabar, orpiment, lead white and carbon black were also identified. The stratigraphic analyses of samples from different locations coupled with SR-XRD analysis indicated the presence of anhydrite, gypsum, calcite and lime in the preparation layer. The pigments identified together with close visual examination showed repainting and retouching within the area in which the Marian figure is depicted, as well as in a nearby figure. The ground preparatory layer consisted of red mud reinforced by straw applied to the chiseled sandstone support. The egg-based binding medium suggests that tempera technique was used. Technical studies of Ethiopian wall paintings are scant, but highly needed as this world heritage is threatened due to limited conservation. Our documentation of the materials and techniques is therefore aimed to stem this loss, as well as to provide information for art historical studies

Challenging an old theory – Portable X-ray fluorescence (pXRF) analyses of greenstone adzes in Rogaland, southwestern Norway

The first large scale regional provenance analysis of greenstone and diabase adzes in western Norway was undertaken forty years ago. The study identified two social territories, which have been central in Norwegian archaeology ever since. Concerns have later been raised regarding the validity of the results due to the dominance of descriptive macroscopic methods, mostly based on visual examinations, used to identify the different rock types. To evaluate the older study, we have undertaken portable X-Ray Fluorescence Spectroscopy (pXRF) analyses of greenstone adzes distributed in Rogaland County, southwestern Norway. However, there are also challenges pertaining to this type of surfaceconfined analytical technique, such as effects of patination, surface depositions, surface geometry and spectral interferences. Methodological rigorousness and proper documentation are thus vital in order to produce valid data suited for inter- and intra-group comparative lithic provenance studies. Acknowledging the concerns raised, we describe our procedure, including the process of selecting suitable parameters and measures taken regarding the computation and replicability of the measurement results. Our preliminary results suggest that pXRF is indeed a capable non-destructive method for studying the provenance of greenstone adzes. It may also prompt further research into the exploitation of rock, place and identity in the Mesolithic

Challenging an old theory – Portable X-ray fluorescence (pXRF) analyses of greenstone adzes in Rogaland, southwestern Norway

The first large scale regional provenance analysis of greenstone and diabase adzes in western Norway was undertaken forty years ago. The study identified two social territories, which have been central in Norwegian archaeology ever since. Concerns have later been raised regarding the validity of the results due to the dominance of descriptive macroscopic methods, mostly based on visual examinations, used to identify the different rock types. To evaluate the older study, we have undertaken portable X-Ray Fluorescence Spectroscopy (pXRF) analyses of greenstone adzes distributed in Rogaland County, southwestern Norway. However, there are also challenges pertaining to this type of surfaceconfined analytical technique, such as effects of patination, surface depositions, surface geometry and spectral interferences. Methodological rigorousness and proper documentation are thus vital in order to produce valid data suited for inter- and intra-group comparative lithic provenance studies. Acknowledging the concerns raised, we describe our procedure, including the process of selecting suitable parameters and measures taken regarding the computation and replicability of the measurement results. Our preliminary results suggest that pXRF is indeed a capable non-destructive method for studying the provenance of greenstone adzes. It may also prompt further research into the exploitation of rock, place and identity in the Mesolithic

Levels of major and trace metals in the leaves and infusions of Croton macrostachyus

The levels of essential metals (Ca, Mg, Fe, Mn, Zn, Cu, Co, Cr, Ni) and toxic metals (Cd, Pb) were determined in the leaves of Croton macrostachyus (traditional medicinal plant) collected from four different regions of Ethiopia (Akaki, Abomsa, Bonga and Dilla) and also in the infusions of leaves collected from Akaki using flame atomic absorption spectrometry. An optimized digestion procedure took 2.5 h for the digestion of 0.5 g of powdered sample with 2 mL of HNO3 and 2 mL of HClO4 at 270 oC while 2 h were needed to digest 25 mL infusion with 4 mL of HNO3 and 1 mL HClO4. The recoveries of metals were in the range 92–103% for the leaves powder and 94–105% for the infusion samples. The mean concentration ranges (mg/g) were Ca (5,823–12,040), Mg (1,971–4,961), Fe (192–581), Mn (157–1,770), Zn (19.5–60.5), Cu (6.31–18.6), Co (1.97–3.45), Cr (2.13–8.75), Ni (2.15–3.80), Cd (0.75–1.08) and Pb (1.05–2.19) for the leave powders and Ca (716–1,776), Mg (16.7–80.9), Fe (1.39–3.34), Mn (2.17–3.40), Zn (0.674–7.88), Cu (1.94–2.31), Co (0.157–0.224), Cr (0.144–1.23), Ni (0.203–0.267), Cd (0.05–0.098) and Pb (0.0148–0.185) for the infusion samples. Among the quantified metals in the infusion samples, Ca showed the highest leaching rate (61.5%) in the 24 h infusion while Fe exhibit the lowest (1%) leaching rate in the 3 h infusion

Arkeologisk undersøkelse av aktivitets- og bosetningsområde ID 177683 fra stein-, bronse- og jernalder, med dyrkingslag, husrester og kokegroper : Sakkastad gnr 36, bnr. 4, Haugesund kommune

Lokaliteten ID 177683 på Sakkastad gnr. 36 i Haugesund kommune ble arkeologisk undersøkt av personale fra Am, UiS i tidsperioden april-juni 2017. De viktigste resultatene fra utgravningen er som følger: • Man påviste sikre, karbondaterte rester (både korn og anleggsspor) etter tidlig dyrking og jordbruksbosetning (senneolitikum – eldre bronsealder) på stedet. Dette er blant de aller eldste sporene etter de første bøndene i denne delen av fylket, og viser at jordbruket var utbredt på denne tiden også i denne delen av Vestlandet. Man fant også spor etter bosetning med korndyrking og avlingshåndtering fra førromersk tid. • Det ble påvist en uvanlig formasjon av ildproduserende anlegg fra førromersk tid, nemlig en tilnærmet rettlinjet «kokegroprekke» bestående av 10 stk. slike anlegg intensjonelt plassert etter hverandre, bare én i bredden. Dette er en type kontekster som er lite kjent fra Vestlandet og Norge, men som er mer utbredt i Sørskandinavia i samme tidsperiode. • De påviste og karbondaterte anleggsporene indikerer at mennesker oppholdt seg jevnlig på stedet fra steinalder til starten av eldre romertid, med innslag av bosetning i huskonstruksjoner. Det ble ikke funnet klare tegn på bosetning her i de senere hundreårene av førreformatorisk tid, dvs. ingen gårdsanlegg fra romertid av og yngre innen lokaliteten. • Pollenanalyse tyder på endringer i landskapet, med avskoging i senneolitikum eller bronsealder etterfulgt av utvidelse av åker- og beitebruk og senere utvikling av lynghei. Dette er i samsvar med landskapsutviklingsprosessen som har blitt påvist av pollenanalyser i andre deler av Rogaland