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[1] High Resolution Stereo Camera (HRSC) images of Hadriaca Patera, Mars, in combination with Mars Orbiter Camera (MOC), Mars Orbiter Laser Altimeter (MOLA), and Thermal Infrared Imaging System (THEMIS) data sets, reveal morphologic details about this volcano and enable determination of a chronology of the major geologic events through new cratering age assessments. New topographic measurements of the Hadriaca edifice were also made from a HRSC-based high-resolution (125 m) digital terrain model (DTM) and compared to the MOLA DTM. We find evidence for a complex formation and erosional history at Hadriaca Patera, in which volcanic, fluvial, and aeolian processes were all involved. Crater counts and associated model ages suggest that Hadriaca Patera formed from early shield-building volcanic (likely explosive pyroclastic) eruptions at $3.7-3.9 Ga, with caldera formation no later than $3.5 Ga. A variety of geologic activity occurred in the caldera and on the northern flank and plains at $3.3-3.5 Ga, likely including pyroclastic flows (that partially filled a large crater NW of the caldera, and plains to the NE) and differential erosion/deposition by aeolian and/or fluvial activity. There were some resurfacing event(s) in the caldera and on the eastern flank at $2.4-2.6 Ga, in which the eastern flank's morphology is indicative of fluvial erosion. The most recent dateable geologic activity on Hadriaca Patera includes caldera resurfacing by some process (most likely differential aeolian erosion/deposition) in the Amazonian Period, as recent as $1.5 Ga. This is coincident with the resurfacing of the heavily channeled south flank by fluvial erosion. Unlike the Tharsis shields, major geologic activity ended at Hadriaca Patera over a billion years ago.

New high-resolution datasets have prompted a mapping-based study of the 2500-km-long Echus Chasma and Kasei Valles system that utilizes geomorphic details, stratigraphic relations, and cratering statistics derived from the new datasets. Our results suggest that between the Hesperian and Amazonian Epochs on Mars (3.7 Ga to Recent) the study area was affected by at least 4 episodes of widespread volcanic activity and 4 periods of episodic fluvio-glacial activity. This paper discusses the Noachian to Hesperian (N2.6 Ga) history of the study area, during which time in the Hesperian three of the volcanic episodes took place along with the first two episodes of fluvioglacial activity. Highlights of our new findings and refinements from this time period include (1) two ancient western floods sourced from Tharsis that occurred around 3.61 and 3.4 Ga and carved the east-trending path of north Kasei Valles; (2) Uranius Dorsum with 58 aligned cones along its length that was emplaced in north Kasei around 3.6 Ga between these periods of early flooding; (3) possible ash deposits surrounding Echus Chasma, one of which contains narrow dendritic valley systems that may have been carved over a period of about 10,000 yr; and (4) evidence that suggests glaciers and near-surface ice may have contributed to erosion of local units.

Spaceborne impact ionization mass spectrometers, such as the Cosmic Dust Analyzer on board the past Cassini spacecraft or the SUrface Dust Analyzer being built for NASA's upcoming Europa Clipper mission, are of crucial importance for the exploration of icy moons in the Solar System, such as Saturn's moon Enceladus or Jupiter's moon Europa. For the interpretation of data produced by these instruments, analogue experiments on Earth are essential. To date, thousands of laboratory mass spectra have been recorded with an analogue experiment for impact ionization mass spectrometers. Simulation of mass spectra of ice grains in space is achieved by a Laser Induced Liquid Beam Ion Desorption (LILBID) approach. The desorbed cations or anions are analyzed in a time‐of‐flight mass spectrometer. The amount of unstructured raw data is increasingly challenging to sort, process, interpret and compare with data from space. Thus far this has been achieved manually for individual mass spectra because no database containing the recorded reference spectra was available. Here we describe the development of a comprehensive, extendable database containing cation and anion mass spectra from the laboratory LILBID facility. The database is based on a Relational Database Management System with a web server interface and enables filtering of the laboratory data using a wide range of parameters. The mass spectra can be compared not only with data from past and future space missions but also mass spectral data generated by other, terrestrial, techniques. The validated and approved subset of the database is available for general public (https://lilbid-db.planet.fu-berlin.de).

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