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Before Perseverance, Jezero crater's floor was variably hypothesized to have a lacustrine, lava, volcanic airfall, or aeolian origin. SuperCam observations in the first 286 Mars days on Mars revealed a volcanic and intrusive terrain with compositional and density stratification. The dominant lithology along the traverse is basaltic, with plagioclase enrichment in stratigraphically higher locations. Stratigraphically lower, layered rocks are richer in normative pyroxene. The lowest observed unit has the highest inferred density and is olivine-rich with coarse (1.5 millimeters) euhedral, relatively unweathered grains, suggesting a cumulate origin. This is the first martian cumulate and shows similarities to martian meteorites, which also express olivine disequilibrium. Alteration materials including carbonates, sulfates, perchlorates, hydrated silicates, and iron oxides are pervasive but low in abundance, suggesting relatively brief lacustrine conditions. Orbital observations link the Jezero floor lithology to the broader Nili-Syrtis region, suggesting that density-driven compositional stratification is a regional characteristic.

We report on a team effort to utilize the M2020 instrument suite to assess the mineralogy of the units we encounter at Jezero. Here, we focus on the possibility of testing orbital observations and hypotheses regarding the olivine-carbonate lithology.

Satellite-derived spectral indices such as the relativized burn ratio (RBR) allow fire severity maps to be produced in a relatively straightforward manner across multiple fires and broad spatial extents. These indices often have strong relationships with field-based measurements of fire severity, thereby justifying their widespread use in management and science. However, satellite-derived spectral indices have been criticized because their non-standardized units render them difficult to interpret relative to on-the-ground fire effects. In this study, we built a Random Forest model describing a field-based measure of fire severity, the composite burn index (CBI), as a function of multiple spectral indices, a variable representing spatial variability in climate, and latitude. CBI data primarily representing forested vegetation from 263 fires (8075 plots) across the United States and Canada were used to build the model. Overall, the model performed well, with a cross-validated R2 of 0.72, though there was spatial variability in model performance. The model we produced allows for the direct mapping of CBI, which is more interpretable compared to spectral indices. Moreover, because the model and all spectral explanatory variables were produced in Google Earth Engine, predicting and mapping of CBI can realistically be undertaken on hundreds to thousands of fires. We provide all necessary code to execute the model and produce maps of CBI in Earth Engine. This study and its products will be extremely useful to managers and scientists in North America who wish to map fire effects over large landscapes or regions.

Acid alteration has long been proposed for the Martian surface, and so it is important to understand how the resulting alteration textures affect surface spectra. Two basaltic materials of varying crystallinity were altered in two different H2SO4 solutions (pH 1 and pH 3) for 220 days. The unaltered and altered samples were studied in the visible and near infrared (VNIR) and thermal infrared (TIR), and select samples were chosen for scanning electron microscopy analysis. Materials altered in pH 3 solutions showed little to no physical alteration, and their spectral signatures changed very little. In contrast, all materials altered in pH 1 acid displayed silica-rich alteration textures, and the morphology differed based on starting material crystallinity. The more crystalline material displayed extensive alteration reaching into the sample interiors and had weaker silica spectral features. The glass sample developed alteration layers tens of microns thick, exhibiting amorphous silica-rich spectral features that completely obscured the substrate. Thus, the strong absorption coefficient of silica effectively decreases the penetration depth of TIR spectral measurements, causing silica abundances to be grossly overestimated in remote sensing data. Additionally, glass samples with silica layers exhibited distinct concave up blue spectral slopes in the VNIR. Spectra from the northern lowland plains of Mars are modeled with high abundances of amorphous silica and exhibit concave up blue spectral slopes and are thus consistent with acid altered basaltic glass. Therefore, we conclude that large regions of the Martian surface may have formed through the interaction of basaltic glass with strongly acidic fluids.

Objectives:- The aims of this investigation were two-fold. First, within the literature no firm conclusions have been drawn about the nature of the psychological and therapeutic needs of individuals with fertility problems. The first section of this investigation, therefore, attempted to explore in more depth the interaction between Clinical Psychologists and the infertile population. Second, research examining the psychology of receiving treatment for infertility (namely, In Vitro Fertilisation - IVF) has largely overlooked the experiences of those for whom treatment has been unsuccessful and a decision to stop has been made. The aim of the second section of the investigation was therefore, to gain a more detailed understanding of the experience of individuals stopping IVF, and to look closely at their adjustment and coping. Design:- Section One - A survey design was employed. Section Two - A qualitative research paradigm using a grounded theory methodology was employed. Method:- Section One - A survey instrument was developed to explore Clinical Psychologists therapeutic contact with persons with fertility problems. Of a total of 1000 questionnaires distributed, a response rate of 43.6 per cent was achieved. Section Two - Eleven participants were recruited from a population of patients who had discontinued unsuccessful IVF treatment. Face-to-face interviews were conducted, exploring participants' feelings and experiences across three areas. (1) their experience of the IVF treatment process; (2) their decision to stop treatment; (3) their lives ‘post decision’. Results:- Section One - only a small proportion of the sample were found to be working with individuals with fertility problems. Female clients were more likely to have been seen therapeutically, with those undergo

Objectives:- The aims of this investigation were two-fold. First, within the literature no firm conclusions have been drawn about the nature of the psychological and therapeutic needs of individuals with fertility problems. The first section of this investigation, therefore, attempted to explore in more depth the interaction between Clinical Psychologists and the infertile population. Second, research examining the psychology of receiving treatment for infertility (namely, In Vitro Fertilisation - IVF) has largely overlooked the experiences of those for whom treatment has been unsuccessful and a decision to stop has been made. The aim of the second section of the investigation was therefore, to gain a more detailed understanding of the experience of individuals stopping IVF, and to look closely at their adjustment and coping. Design:- Section One - A survey design was employed. Section Two - A qualitative research paradigm using a grounded theory methodology was employed. Method:- Section One - A survey instrument was developed to explore Clinical Psychologists therapeutic contact with persons with fertility problems. Of a total of 1000 questionnaires distributed, a response rate of 43.6 per cent was achieved. Section Two - Eleven participants were recruited from a population of patients who had discontinued unsuccessful IVF treatment. Face-to-face interviews were conducted, exploring participants' feelings and experiences across three areas. (1) their experience of the IVF treatment process; (2) their decision to stop treatment; (3) their lives ‘post decision’. Results:- Section One - only a small proportion of the sample were found to be working with individuals with fertility problems. Female clients were more likely to have been seen therapeutically, with those undergo