Forced Confessions of a Lover

Title of Document: FORCED CONFESSION OF A LOVER Alexander R Peace, MFA, 2012 Directed By: Professor WC Richardson, Department of Art I believe in Painting, the moment the historic and the autobiographic collapse within a single frame

Structural inheritance and magmatism during continental breakup in West Greenland and Eastern Canada

Continental extension causes rifting and thinning of the lithosphere that may result in breakup and eventually the initiation of seafloor spreading and passive continental margin development. Ambiguity exists regarding the roles of magmatism and structural inheritance during rifting and continental breakup during this process. This study focuses on the importance of these controls on the Mesozoic-Cenozoic separation between West Greenland and Eastern Canada. It is important to improve our knowledge of the processes that influenced breakup as the current understanding of these processes is limited and also to reduce hydrocarbon exploration risk in this tectonic setting. During this study passive margin processes were investigated using a variety of methodologies at a range of scales from that of conjugate margin pairs (Chapters 4 and 5), through margin and basin scale studies (Chapter 6) to the smallest scale on individual igneous intrusions (Chapter 7). At the largest scale an assessment of the magmatic and structural asymmetry between the conjugate margins of the Labrador Sea based primarily on field data and subsequent analysis near Makkovik, Labrador, but also other large-scale geophysical datasets demonstrated that early rifting was dominated by simple shear rather than pure shear. In such a scenario Labrador was have been the lower plate margin to the upper plate southwest Greenland margin. Further analysis of field observations indicated that rifting of the Labrador Sea region may have been aided by a favourably orientated basement metamorphic fabric and that observable onshore brittle deformation structures may be related to Mesozoic rifting. Further north in the Davis Strait, seismic interpretation at the margin and basin scale allowed a series of seismic surfaces, isochrons and a new offshore fault map to be produced. The results of this analysis demonstrated that the geometry of rift basins was primarily controlled by pre-existing structures, an assertion supported by observations of reactivation onshore in West Greenland. Finally, at the smallest scale, results of numerical modelling offshore Newfoundland demonstrated that even on non- volcanic passive margins, intrusive magmatism can influence thermal evolution. In addition, the presence of widespread igneous rocks on passive margins may be indicative of regional-scale thermal perturbations that should be considered in source rock maturation studies. Overall, the conclusion of this project is that both magmatism and structural inheritance have profoundly influenced the continental breakup between West Greenland and Eastern Canada, and that interplay between these two complex groups of mechanisms may have also contributed to the geological evolution of this area

The crustal structure in the Northwest Atlantic region from receiver function inversion – Implications for basin dynamics and magmatism

The Labrador Sea and Baffin Bay form an extinct Palaeogene oceanic spreading system, divided by a major continental transform, the Davis Strait, with the whole region defined as the Northwest Atlantic. The Davis Strait hosts the Ungava Fault Zone and is the central structural element of the Davis Strait Large Igneous Province (DSIP) that formed broadly coeval with continental breakup to its north and south. While constraints on the crustal structure in this region primarily exist in the offshore, crustal models are limited onshore, which makes an interpretation of regional structures as well as the extent, and therefore origin of the DSIP extremely difficult to ascertain. Here, we have collected all available teleseismic data from the Northwest Atlantic margins and applied a receiver function inversion to retrieve station-wise velocity models of the crust and uppermost mantle. We integrate the outcomes with published controlled-source seismic data and regional crustal models to make inferences about the crustal structure and evolution of the Northwest Atlantic. In particular, we focused on constraining the spatial extent and origin of high velocity lower crust (HVLC), and determining whether it is generically related to the Davis Strait Igneous Province, syn-rift exhumed and serpentinised mantle, or pre-existing lower crustal bodies such as metamorphosed lower crust or older serpentinised mantle rocks. The new results allow us to better spatially constrain the DSIP and show the possible spatial extent of igneous-type HVLC across Southwest Greenland, Northwest Greenland and Southeast Baffin Bay. Similarly, we are able to relate some HVLC bodies to possible fossil collision/subduction zones/terrane boundaries, and in some instances to exhumed and serpentinised mantle.publishedVersio

Investigating the Goban Spur rifted continental margin, offshore Ireland, through integration of new seismic reflection and potential field data

The Goban Spur, offshore Ireland, is a magma-poor rifted continental margin conjugate to the well-studied Newfoundland margin, offshore Canada. Published studies demonstrated that a 70-km-wide zone of exhumed serpentinized mantle lies between oceanic crust and stretched continental crust at the seaward limit of Goban Spur. However, the along-strike extent of this serpentinized zone has, until now, been unknown due to insufficient data coverage. The crustal architecture of the margin is complicated due to its multi-staged tectonic history. Here, six newly acquired multi-channel seismic reflection lines are processed and interpreted, along with vintage seismic profiles, to characterize its structure and evolution. These seismic profiles reveal significant along-strike structural variations along the Goban Spur margin, and allow us to delimit five distinct crustal zones related to different rifting stages and their regional extents. The geometries of each crustal domain are variable along the margin strike, probably suggestive of different extension rates during the evolution of the margin or inherited variations in crustal composition and rheology. The transitional zone between oceanic crust and stretched continental crust consists of both shallow peridotite ridges and deeper exhumed serpentinized mantle, much like the conjugate Iberian and Newfoundland margins. Above the top basement in the exhumed domain, the syn-exhumed sediments show strikingly weak reflectivity, rarely seen at other magma-poor margins. Magmatic events occur coincident with each rifting stage, and the volume of magmatic accretions increases from NW to SE, more than previously interpreted. Plate reconstruction of the Goban Spur and its possible conjugate – the Flemish Cap, shows asymmetry in the crustal architectures, likely due to rift evolution involving more 3-D complexity than can be explained by simple 2-D extensional kinematics

Evolution of Labrador Sea–Baffin Bay: Plate or Plume Processes?

Breakup between Greenland and Canada resulted in oceanic spreading in the Labrador Sea and Baffin Bay. These ocean basins are connected through the Davis Strait, a bathymetric high comprising primarily continental lithosphere, and the focus of the West Greenland Tertiary volcanic province. It has been suggested that a mantle plume facilitated this breakup and generated the associated magmatism. Plume-driven breakup predicts that the earliest, most extensive rifting, magmatism and initial seafloor spreading starts in the same locality, where the postulated plume impinged. Observations from the Labrador Sea–Baffin Bay area do not accord with these predictions. Thus, the plume hypothesis is not confirmed at this locality unless major ad hoc variants are accepted. A model that fits the observations better involves a thick continental lithospheric keel of orogenic origin beneath the Davis Strait that blocked the northward-propagating Labrador Sea rift resulting in locally enhanced magmatism. The Davis Strait lithosphere was thicker and more resilient to rifting because the adjacent Paleoproterozoic Nagssugtoqidian and Torngat orogenic belts contain structures unfavourably orientated with respect to the extensional stress field at the time

The African continental divide: Indian versus Atlantic Ocean spreading during Gondwana dispersal

It is well established that plate-tectonic processes operate on a global scale and that spatially separate but temporally coincident events may be linked. However, identifying such links in the geological record and understanding the mechanisms involved remain speculative. This is particularly acute during major geodynamic events, such as the dispersal of supercontinents, where multiple axes of breakup may be present as well as coincidental collisional events. To explore this aspect of plate tectonics, we present a detailed analysis of the temporal variation in the mean half rate of seafloor spreading in the Indian and Atlantic Oceans, as well as plate-kinematic attributes extracted from global plate-tectonic models during the dispersal of Gondwana since ca. 200 Ma. Our analysis shows that during the ~20 m.y. prior to collision between India and Asia at ca. 55 Ma, there was an increase in the mean rate of seafloor spreading in the Indian Ocean. This manifests as India rapidly accelerating toward Asia. This event was then followed by a prompt deceleration in the mean rate of Indian Ocean seafloor spreading after India collided with Asia at ca. 55 Ma. Since inception, the mean rate of seafloor spreading in the Indian Ocean has been generally greater than that in the Atlantic Ocean, and the period of fastest mean half spreading rate in the Indian Ocean was coincident with a slowdown in mean half seafloor spreading rate in the competing Atlantic Ocean. We hypothesize that faster and hotter seafloor spreading in the Indian Ocean resulted in larger ridge-push forces, which were transmitted through the African plate, leading to a slowdown in Atlantic Ocean spreading. Following collision between India and Asia, and a slowdown of Indian Ocean spreading, Atlantic spreading rates consequently increased again. We conclude that the processes in the Indian and Atlantic Oceans have likely remained coupled throughout their existence, that their individual evolution has influenced each other, and that, more generally, spreading in one basin inevitably influences proximal regions. While we do not believe that ridge push is the main cause of plate motions, we consider it to have played a role in the coupling of the kinematic evolution of these oceans. The implication of this observation is that interaction and competition between nascent ocean basins and ridges during supercontinent dispersal exert a significant control on resultant continental configuration.N/

The role of pre-existing structures during rifting, continental breakup and transform system development, offshore West Greenland

Continental breakup between Greenland and North America produced the small oceanic basins of the Labrador Sea and Baffin Bay, which are connected via the Davis Strait, a region mostly comprised of continental crust. This study contributes to the debate regarding the role of pre-existing structures on rift development in this region using seismic reflection data from the Davis Strait data to produce a series of seismic surfaces, isochrons and a new offshore fault map from which three normal fault sets were identified as (i) NE-SW, (ii) NNW-SSE and (iii) NW-SE. These results were then integrated with plate reconstructions and onshore structural data allowing us to build a two-stage conceptual model for the offshore fault evolution in which basin formation was primarily controlled by rejuvenation of various types of pre-existing structures. During the first phase of rifting between at least Chron 27 (ca. 62 Ma; Palaeocene), but potentially earlier, and Chron 24 (ca. 54 Ma; Eocene) faulting was primarily controlled by pre-existing structures with oblique normal reactivation of both the NE-SW and NW-SE structural sets in addition to possible normal reactivation of the NNW-SSE structural set. In the second rifting stage between Chron 24 (ca. 54 Ma; Eocene) and Chron 13 (ca. 35 Ma; Oligocene), the sinistral Ungava transform fault system developed due to the lateral offset between the Labrador Sea and Baffin Bay. This lateral offset was established in the first rift stage possibly due to the presence of the Nagssugtoqidian and Torngat terranes being less susceptible to rift propagation. Without the influence of pre-existing structures the manifestation of deformation cannot be easily explained during either of the rifting phases. Although basement control diminished into the post-rift, the syn-rift basins from both rift stages continued to influence the location of sedimentation possibly due to differential compaction effects. Variable lithospheric strength through the rifting cycle may provide an explanation for the observed diminishing role of basement structures through time

Basic Mechanisms of Immunometabolites in Shaping the Immune Response

Background: Innate immune cells play a crucial role in responding to microbial infections, but their improper activation can also drive inflammatory disease. For this reason, their activation state is governed by a multitude of factors, including the metabolic state of the cell and, more specifically, the individual metabolites which accumulate intracellularly and extracellularly. This relationship is bidirectional, as innate immune cell activation by pathogen-associated molecular patterns causes critical changes in cellular metabolism. Summary: In this review, we describe the emergence of various “immunometabolites.” We outline the general characteristics of these immunometabolites, the conditions under which they accumulate, and their subsequent impact on immune cells. We delve into well-studied metabolites of recent years, such as succinate and itaconate, as well as newly emerging immunometabolites, such as methylglyoxal. Key Messages: We hope that this review may be used as a framework for further studies dissecting the mechanisms by which immunometabolites regulate the immune system and provide an outlook to harnessing these mechanisms in the treatment of inflammatory diseases

Earth Science Education #7. GeoTrails: Accessible Online Tools for Outreach and Education

As geoscientists, we must prioritize improving our ability to communicate science to the public. Effective geoscience communication enables communities to understand how geological processes have shaped our planet and make informed decisions about Earth’s future. However, geoscience research outputs have traditionally been published in peer-reviewed journals and presented at academic conferences. Consequently, essential information about local geology is rarely available in accessible, open access, and engaging formats. Here, we propose virtual field trips, or ‘GeoTrails’, as a possible solution to address the disconnect between geoscience research and public knowledge by improving our communication to the public. This initiative is largely driven by undergraduate students, who identify points of geological interest along selected hiking trails, write concise descriptions derived from scientific sources (e.g. longer peer-reviewed articles and government reports), and collect field data (e.g. 3-D LiDAR models, drone photography) to illustrate the characteristics of these geological features. The goal of the project is to communicate the importance of local geology on our environment and to raise awareness of how changing climates could affect us in the future; this information can empower communities to make better, more informed planning decisions. The creation of GeoTrails along the Niagara Escarpment offers a promising strategy to highlight the role of geoscientists and to engage the public in our ongoing research that aims to showcase Canada’s geoheritage.En tant que géoscientifiques, nous devons donner la priorité à l’amélioration de notre capacité à communiquer la science au public. Une communication efficace des géosciences permet aux communautés de comprendre comment les processus géologiques ont façonné notre planète et de prendre des décisions éclairées sur l’avenir de la Terre. Cependant, les résultats de la recherche en géosciences ont traditionnellement été publiés dans des revues à comité de lecture et présentés lors de conférences académiques. Par conséquent, les informations essentielles sur la géologie locale sont rarement disponibles sous des formats accessibles, en libre accès et attrayants. Dans cette optique, nous proposons des excursions virtuelles, ou « GeoTrails », comme solution possible pour combler le fossé entre la recherche en géosciences et la connaissance du public en améliorant notre communication avec celui-ci. Cette initiative est en grande partie menée par des étudiants de premier cycle, qui identifient des points d’intérêt géologiques le long de sentiers de randonnée sélectionnés, rédigent des descriptions concises basées sur des sources scientifiques (par exemple, des articles à comité de lecture plus longs et des rapports gouvernementaux) et collectent des données sur le terrain (par exemple, des modèles LiDAR 3-D, des photographies par drone) pour illustrer les caractéristiques de ces caractéristiques géologiques. L'objectif du projet est de communiquer l'importance de la géologie locale sur notre environnement et de sensibiliser aux façons dont les changements climatiques pourraient nous affecter à l'avenir; cette information peut permettre aux communautés de prendre des décisions de planification meilleures et plus éclairées. La création de GeoTrails le long de l'escarpement du Niagara offre une stratégie prometteuse pour mettre en valeur le rôle des géoscientifiques et pour engager le public dans notre recherche en cours qui vise à présenter le patrimoine géologique du Canada

Allele-informed copy number evaluation of plasma DNA samples from metastatic prostate cancer patients: the PCF_SELECT consortium assay

Sequencing of cell-free DNA (cfDNA) in cancer patients' plasma offers a minimally-invasive solution to detect tumor cell genomic alterations to aid real-time clinical decision-making. The reliability of copy number detection decreases at lower cfDNA tumor fractions, limiting utility at earlier stages of the disease. To test a novel strategy for detection of allelic imbalance, we developed a prostate cancer bespoke assay, PCF_SELECT, that includes an innovative sequencing panel covering ∼25 000 high minor allele frequency SNPs and tailored analytical solutions to enable allele-informed evaluation. First, we assessed it on plasma samples from 50 advanced prostate cancer patients. We then confirmed improved detection of genomic alterations in samples with <10% tumor fractions when compared against an independent assay. Finally, we applied PCF_SELECT to serial plasma samples intensively collected from three patients previously characterized as harboring alterations involving DNA repair genes and consequently offered PARP inhibition. We identified more extensive pan-genome allelic imbalance than previously recognized in prostate cancer. We confirmed high sensitivity detection of BRCA2 allelic imbalance with decreasing tumor fractions resultant from treatment and identified complex ATM genomic states that may be incongruent with protein losses. Overall, we present a framework for sensitive detection of allele-specific copy number changes in cfDNA