Middle-Late Ordovician Mt. Wilson Quartzite, southern British Columbia, Canada, is a supermature quartz arenite deposited in shallow marine-marginal marine environments on the Early Paleozoic western Laurentian passive margin. Facies-stacking patterns indicate the Mt. Wilson Quartzite is an unconformity bounded, 2nd-order depositional sequence, containing two 3rd-order sequences, and numerous parasequences. Detrital zircon age spectra of six samples of the Mt. Wilson Quartzite have numerous peaks that are unique to Middle to Late Ordovician quartz arenites of western Laurentia. The main peaks, 1800-2000 Ma, 2000-2200 Ma, and 2300-2400 Ma are interpreted to have been derived from basement rocks that were exposed east of the study area: Trans-Hudson Orogeny (1800-2000 Ma), Taltson Orogen (1800-2000 Ma), Buffalo Head Terrane (2000-2400 Ma), Paleoproterozoic crust (2000-2400 Ma), and the Wopmay Terrane (2000-2400 Ma). It is likely that these areas were sourced by local rivers and tributaries draining the Transcontinental Arch and delivered sediment to the deposition location of the Mt. Wilson Quartzite. While longshore transport was a viable distribution method for sediment along the passive margin, it is unlikely that the Peace River Arch (located northwest of the Mt. Wilson Quartzite) was its sole point source; rather it is more likely that there were multiple sediment sources for these western Laurentian quartz arenites. Temporal changes in provenance indicate different areas of basement rock were exposed throughout the deposition of the Mt. Wilson Quartzite, most likely reflecting long-term flooding of North America. The potential for spatial changes in provenance remains unsolved.

Middle Ordovician (Whiterockian) sandstone units within the Oil Creek, McLish, and Tulip Creek formations of the Simpson Group of Oklahoma, and the Everton (Calico Rock Member) and St. Peter formations of Arkansas were deposited on the southern margin of Laurentia. They represent the first major siliciclastic input to the southern U.S. Midcontinent above the post-Sauk unconformity. Samples were collected from outcrops of the major sandstone units to determine their U-Pb detrital zircon age distributions for provenance. Samples were prepared and analyzed using laser ablation - inductively coupled plasma - mass spectrometry (LA-ICP-MS). Probability-density plots were created to determine likely source areas for sediment, based on comparing detrital zircon ages to known ages of basement terranes. Detrital zircon grains from the Early Whiterockian Calico Rock sandstone indicate a majority of its zircon population was ultimately derived from the 900-1300 Ma Grenville orogenic province, with secondary input ultimately derived from the 1300-1550 Ma Granite-Rhyolite/Anorogenic Province and the Archean Superior province along the Transcontinental Arch. It is likely, at this time, that zircons were also sourced from reworked sediments from more proximal secondary sources. With sea level rise and transgression, the depositional shoreline and the sediment source areas moved to the north and west. The basal Oil Creek Sandstone of the Simpson Group was deposited unconformably above the Arbuckle Group in southern Oklahoma, and its zircon population is dominated by grains from Archean source terranes along the Transcontinental Arch. The basal sandstone unit of the McLish Formation indicates renewed sediment input containing zircons from 1300-1550 Ma Granite-Rhyolite/Anorogenic and 1600-1700 Ma Yavapai-Mazatzal terranes along the Transcontinental Arch. The Nemaha Ridge in northeastern Kansas likely acted as a source of first-cycle sediment in the southern midcontinent during this time. Small populations of detrital zircon grains between 1800 Ma and 2000 Ma occur in the majority of the samples. Their probability density peaks are generally centered at roughly 1850 Ma, suggesting an ultimate source in the Penokean orogenic province along the Transcontinental Arch.

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I denna uppsats analyseras utbredningen av fornlämningar i Mälardalen och deras förhållande till miljö och geologi, med fokus på att hitta okända fornlämningar med hjälp av digitala verktyg. Kulturmiljöregistret baserat på inventeringar genomförda över tid studeras. Verktygen GIS och MaxEnt beskrivs, samt deras användning för arkeologiska landskapsstudier. De används för analys av fornlämningarnas spridningsbild. Ett antal lämningskategorier valdes ut för analys, och resultaten jämförs med tidigare forskning. Arkeologi och statistik kombinerat med naturvetenskapliga metoder används för att skapa modeller av okända lämningar som kan användas för att försöka återfinna dessa genom historiska kartor, LiDAR eller med geofysik. Spridningsmönster av figurristningar från bronsåldern påvisas ha en stark korrelation till bergarten kvartsarenit, en upptäckt som kan leda till nya tolkningar av lämningskategorin och landskapsutnyttjandet i Uppland. Uppsatsen visar på modeller och tekniker för landskapsanalys som kan vara användbara för att identifiera tidigare okända mönster och bättre förstå förhistoriska landskap samt för att skapa en brygga till framtida arkeologisk forskning med stöd av AI, drönare och stora datamängder. / In this paper, the distribution of ancient remains in the Mälardalen and their relationship to the environment and geology is analysed, focusing on finding unknown ancient remains using digital tools. Kulturmiljöregistret created from inventories carried out over time is studied. The tools GIS and MaxEnt are described, as well as their use for archaeological landscape studies and for analysis of distribution patterns of ancient remains. A number of categories of remains were selected for analysis, and the results were compared with previous research. Archaeology and statistics combined with natural science are used to create models of unknown remains for recovering them with the aid of historical maps, LiDAR or geophysics. Distribution patterns of figure carvings from the Bronze Age are shown to have a strong correlation to the rock type quartz arenite, a discovery that can lead to new interpretations of this category of remains and the landscape utilization in Uppland. The paper shows models for landscape analysis which can be useful for identifying previously unknown patterns and for better understanding of prehistoric landscapes, as well as to create a bridge to future archaeological research supported by AI, drones and large data sets.