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Abstract The Enriquillo–Plantain Garden fault (EPGF), the southern branch of the northern Caribbean left-lateral transpressional plate boundary, has ruptured in two devastating earthquakes along the Haiti southern peninsula: the Mw 7.0, 2010 Haiti and the Mw 7.2, 2021 Nippes earthquakes. In Jamaica, the 1692 Port Royal and 1907 Great Kingston earthquakes caused widespread damage and loss of life. No large earthquakes are known from the 200-km-long Jamaica Passage segment of this plate boundary. To address these hazards, a National Science Foundation Rapid Response survey was conducted to map the EPGF in the Jamaica Passage south of Kingston, Jamaica, and east of the island of Jamaica. From the R/V Pelican we collected >50 high-resolution seismic profiles and 47 gravity cores. Event deposits (EDs) were identified from lithology, physical properties, and geochemistry and were dated in 13 cores. A robust 14C chronology was obtained for the Holocene. A Bayesian age model using OxCal 4.4 calibration was applied. Out of 58 EDs that were recognized, 50 have ages that overlap within their 95% confidence ranges. This allowed for their grouping in multiple basins located as much as 150 km apart. The significant age overlap suggests that EDs along the Enriquillo–Plantain Garden plate boundary resulted from large and potentially dangerous earthquakes. Most of these earthquakes may derive from the EPGF but also from thrust faulting at this strain-partitioned transpressional boundary. The recent increase in Coulomb stress on the EPGF from the Mw 7.2 Nippes earthquake in southwestern Haiti and the discoveries reported here enhance the significance for hazard in the Jamaica Passage. 

Abstract The Unlearning Racism in Geosciences (URGE) program guides groups of geoscientists as they draft, implement, and assess anti‐racist policies and resources for their workplace. Some participating Geoscientists of Color (GoC) shared concerns about microaggression, tokenism, and power struggles within their groups. These reports led us to collect and analyze data that describe the experiences of GoC in URGE. The data are from five discussion groups and two surveys. Our analyses revealed that participating GoC want to continue working with White colleagues on anti‐racist work. GoC want White colleagues not to shy away from doing anti‐racist work. Instead, GoC want White colleagues (a) to create and adhere to robust behavioral codes of conduct, (b) to focus discussions on anti‐racism, (c) to act on anti‐racism initiatives, (d) not to prompt GoC to educate them or reveal trauma, and (e) to refrain from microaggressions and tokenism. These desired outcomes were achieved in some groups with varying degrees of success. Correcting a history of mistrust relating to racism and anti‐racism action is key to implementing and assessing effective anti‐racist policies and resources. This requires leadership support, following through on anti‐racism action, and deepening relationships between GoC and White colleagues. Future anti‐racist programs should spend a substantial amount of time on and demonstrate the importance of training participants how to discuss racism effectively and how to create and adhere to robust behavioral codes of conduct. Future programs should also explore developing a robust program‐wide code of conduct that includes a policy for reporting offenses. 

Abstract We quantify the volume and distribution of water, cement, sediments, and fractured rocks within the Martian crust beneath NASA's InSight (Interior Exploration using Seismic Investigations, Geodesy, and Heat Transport mission) lander by using rock physics models to interpret shear wave velocities (V_s) measured from InSight data. The models assume that Mars' crust comprises sediments and fractured rocks whose pores and fractures host variable combinations of gas, liquid water, and mineral cements. MeasuredV_sin the upper crust (0–8 km) can be explained by layers of minimally (<2%) cemented sediments and gas‐filled fractured basalts. MeasuredV_sin the deeper crust (8–20 km) can be explained by fractured basalts or more felsic igneous rocks (modeled here as 100% plagioclase feldspar) that is unfractured or has up to 23% porosity. Open pores in the deeper crust could host gas, liquid water, and up to 2% cement. ModeledV_sare too low for a seismically detectable ice‐saturated cryosphere in the upper crust and temperatures are too high to freeze liquid water in the deeper crust. Notably, withV_salone, we are unable to distinguish between liquid water and gas within the pores. 

Abstract Ice and other mineral cements in Mars' shallow subsurface affect the mechanical properties of the shallow crust, the geologic processes that shape the planet's surface, and the search for past or extant Martian life. Cements increase seismic velocities. We use rock physics models to infer cement properties from seismic velocities. Model results confirm that the upper 300 m of Mars beneath InSight is most likely composed of sediments and fractured basalts. Grains within sediment layers are unlikely to be cemented by ice or other mineral cements. Hence, any existing cements are nodular or formed away from grain contacts. Fractures within the basalt layers could be filled with gas, 2% mineral cement and 98% gas, and no more than 20% ice. Thus, no ice‐ or liquid water‐saturated layers likely exist within the upper 300 m beneath InSight. Any past cement at grain contacts has likely been broken by impacts or marsquakes.