Geology topics

C. Amos

Publications and source records attributed to C. Amos.

2 recordsLinked to original sources

USGS2021

Solar-system-wide significance of Mars polar science

1. The North Polar Layered Deposits contain thousands of ice layers that record accumulation and climate history for at least several million years, making the most accessible and most complete climate record aside from the Earth’s – and the only one to record the impact of large obliquity shifts. 2. Mars Polar Science is a diverse and integrated system spanning much of the planet, above and below the surface: geographic poles, mid- and high-latitudes, numerous active volatile processes that interact with the near-surface, and the lower and middle atmosphere circulations, even influencing the upper atmosphere and atmospheric escape. 3. Mars polar processes serves as an analogue and scientific link to numerous solar system bodies. Mars has two volatile cycles that influence surface processes, atmospheric processes, and climate cycles. Mars, with many data sets and observations, serves as a proxy for outer planets and moons that undergo the same physics but with other volatile species. Additionally, technology designed for Mars polar exploration benefits exploration elsewhere. 4. Mars Polar and Atmospheric Science results are critical for future human exploration and in situ resources and the study of planetary habitability.

Bulletin of the AAS↗

USGS2018

Holocene surface rupture history of an active forearc fault redefines seismic hazard in Southwestern British Columbia, Canada

Characterizing the hazard associated with Quaternary‐active faults in the forearc crust of the northern Cascadia subduction zone has proven challenging due to historically low rates of seismicity, late Quaternary glacial scouring, and dense vegetation that often obscures fault‐related geomorphic features. We couple lidar topography with paleoseismic trenching across the Leech River Fault on southern Vancouver Island to produce the first detailed surface rupture history of an onland forearc fault in British Columbia, Canada. The results indicate that this fault produced three surface‐rupturing earthquakes in the last ∼9 kyr and is therefore capable of producing large (Mw>6) earthquakes in the future. We provide new constraints on the fault's length (∼130 km) and Holocene slip rate (≥0.2–0.3 mm/year) that, together with the earthquake ages, should be incorporated into new seismic hazard assessments and building code practices relevant to urban centers in southwestern British Columbia (Canada) and northwestern Washington State (United States).

British Columbia↗