Geology of the Kuiper quadrangle (H06), Mercury

The geological map is available as supplemental material at: https://www.tandfonline.com/doi/suppl/10.1080/17445647.2022.2035268The Kuiper quadrangle (H06) is located at the equatorial zone of Mercury and encompasses the area between 288°E–360°E and 22.5°N–22.5°S. Using the NASA MESSENGER data, we compiled a geological map of the quadrangle at a 1:3,000,000 scale. The mapping was mainly based on photo-interpretation of an MDIS (Mercury Dual Imaging System) monochrome 166 m/pixel basemap. Additional datasets were also considered: stereo-DTM of the region, mosaics with high-incidence illumination, and the MDIS global color mosaic. The map shows that the quadrangle is characterized by the prevalence of crater materials which are distinguished into three classes based on their degradation degree. Different plain units were also identified and classified on the basis of their density of cratering. Several structures, mainly represented by contractional faults, were mapped in all quadrangle areas. The map represents the first complete geologic survey of H06 at this scale and provides a highly detailed analysis of the Kuiper quadrangle’s surface geology

Rationale for BepiColombo Studies of Mercury's Surface and Composition

BepiColombo has a larger and in many ways more capable suite of instruments relevant for determination of the topographic, physical, chemical and mineralogical properties of Mercury's surface than the suite carried by NASA's MESSENGER spacecraft. Moreover, BepiColombo's data rate is substantially higher. This equips it to confirm, elaborate upon, and go beyond many of MESSENGER's remarkable achievements. Furthermore, the geometry of BepiColombo's orbital science campaign, beginning in 2026, will enable it to make uniformly resolved observations of both northern and southern hemispheres. This will offer more detailed and complete imaging and topographic mapping, element mapping with better sensitivity and improved spatial resolution, and totally new mineralogical mapping. We discuss MESSENGER data in the context of preparing for BepiColombo, and describe the contributions that we expect BepiColombo to make towards increased knowledge and understanding of Mercury's surface and its composition. Much current work, including analysis of analogue materials, is directed towards better preparing ourselves to understand what BepiColombo might reveal. Some of MESSENGER's more remarkable observations were obtained under unique or extreme conditions. BepiColombo should be able to confirm the validity of these observations and reveal the extent to which they are representative of the planet as a whole. It will also make new observations to clarify geological processes governing and reflecting crustal origin and evolution. We anticipate that the insights gained into Mercury's geological history and its current space weathering environment will enable us to better understand the relationships of surface chemistry, morphologies and structures with the composition of crustal types, including the nature and mobility of volatile species. This will enable estimation of the composition of the mantle from which the crust was derived, and lead to tighter constraints on models for Mercury's origin including the nature and original heliocentric distance of the material from which it formed.Peer reviewe

Fatality rate and predictors of mortality in an Italian cohort of hospitalized COVID-19 patients

Clinical features and natural history of coronavirus disease 2019 (COVID-19) differ widely among different countries and during different phases of the pandemia. Here, we aimed to evaluate the case fatality rate (CFR) and to identify predictors of mortality in a cohort of COVID-19 patients admitted to three hospitals of Northern Italy between March 1 and April 28, 2020. All these patients had a confirmed diagnosis of SARS-CoV-2 infection by molecular methods. During the study period 504/1697 patients died; thus, overall CFR was 29.7%. We looked for predictors of mortality in a subgroup of 486 patients (239 males, 59%; median age 71 years) for whom sufficient clinical data were available at data cut-off. Among the demographic and clinical variables considered, age, a diagnosis of cancer, obesity and current smoking independently predicted mortality. When laboratory data were added to the model in a further subgroup of patients, age, the diagnosis of cancer, and the baseline PaO2/FiO2 ratio were identified as independent predictors of mortality. In conclusion, the CFR of hospitalized patients in Northern Italy during the ascending phase of the COVID-19 pandemic approached 30%. The identification of mortality predictors might contribute to better stratification of individual patient risk

GEOLOGICAL MAPPING AND ANALYSIS OF DAEDALIA PLANUM LAVA FIELD (MARS)

Volcanism is the most important rock-forming processes of the planetary surfaces and represents one of the main clues to investigate the chemical composition of the interior and the thermal history of a planet. Our study has been focused on the Daedalia Planum volcanic region, located to south-west of Arsia Mons, where some of the longest lava flows on Mars were emplaced. THEMIS, MOC and HiRISE images were analyzed in order to perform a stratigraphic and morphological analysis of the area and realize a Daedalia Planum geological map where different flow units are represented. Several features observed on the flow surface have been interpreted as related to inflation processes on the basis of several similarities with the morfologies of the inflated terrestrial Payen Matru flows (Argentina). This suggests that inflation process is quite common for the Daedalia Planum field, implying that the inflation emplacement mechanism on Martian flows could be more frequent than previously supposed and, consequently, effusion rates and rheological properties of Martian lavas more variable. In addition, a comparative study performed between the mounds detected on Daedalia Planum and Elysium Planitia regions seems to further confirm the tumuli nature of the Daedalia Planum features and thus the presence of inflated flows in this volcanic field. The OMEGA data reveal that Daedalia Planum lavas have a spectral response coherent with a basaltic composition. In addition the Spectral Angle Mapper (SAM) classification obtained from the OMEGA data highlights that the flows are characterized by distinctive spectral responses, which should depend on non-compositional factors, like different surface textures of flows but also different mineralogy or rock texture, such as the presence of glass, crystal size or crystal isoorientation.Il vulcanismo è uno dei più importanti processi che interessano la superficie di un pianeta e rappresenta una delle chiavi per investigare la composizione chimica del suo interno nonché la sua storia termica. Il nostro studio si è focalizzato sul campo vulcanico di Daedalia Planum, a sud ovest di Arsia Mons, dove si trovano alcune delle più lunghe colate conosciute su Marte. Varie immagini di THEMIS, MOC e HiRISE sono state analizzate con l'obiettivo di studiare questa regione sia dal punto di vista stratigrafico che morfologico e di creare una mappa geologica della regione. Da questa analisi sono state individuate varie forme interpretate come collegate al processo di inflation e il confronto con le colate inflate terrestri del Payen (Argentina) sembrano confermare tale ipotesi. Ciò suggerisce che l’inflation è piuttosto comune nel capo lavico di Daedalia Planum e che, in generale, questo processo interessi più colate di Marte di quanto supposto finora. Di conseguenza i tassi di eruzione e le proprietà reologiche delle lave su Marte potrebbero essere molto più variabili. Uno studio comparativo tra le forme a cupola individuate su Daedalia Planum ed Elysium Planitia confermerebbe ulteriormente che su Daedalia Planum vi è effettivamente la presenza di tumuli e, quindi, di colate laviche inflate. Infine, prendendo in considerazione i dati OMEGA della regione, si è appurato che le lave presenti su Daedalia Planum hanno una risposta spettrale coerente con una composizione basaltica. Le classificazioni SAM ottenute da dati OMEGA evidenziano, inoltre, come le colate della regione siano effettivamente caratterizzate da distinte risposte spettrali, verosimilmente attribuibili a fattori non composizionali quali la diversa tessitura superficiale o la differente mineralogia e tessitura della roccia, come la presenza di vetro, la dimensione dei cristalli o la loro isoorientazione

DATING THRUST SYSTEM ON MERCURY.

Mercury is a planet dominated by contractional features at a global scale. The age deter-mination of these features will permit to estimate the rate of global contraction and whether limits could be placed on when the contraction occurred. This will give us new clues to better understanding the thermal evolution of the planet