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USGS2021

Risk-informed levee erosion countermeasure site selection and design in the Sacramento area part 1: Soil sampling, testing, and data processing

USACE partnered with the United States Department of Agriculture, Agricultural Research Service, United States Geological Survey, and Texas A&M University to evaluate the erodibility of the river banks and levees to inform probabilistic numerical simulations using the Bank Stability and Toe Erosion Model (BSTEM). This paper discusses the measurement of the intrinsic erosion and geotechnical properties of the soil for improved BSTEM results and is the first of two parts. Sampling and testing were conducted at select sites to obtain the soil stratigraphy and collect samples for estimation of engineering properties. Soil erodibility was measured using the Erosion Function Apparatus test, the Borehole Erosion Test, the Pocket Erodometer Test, and the mini-Jet Erosion Test. Critical evaluation of previously existing datasets and the collection of these new datasets helped to provide better definition of the range in erosion parameters for improved probabilistic erosion estimates using BSTEM for risk-informed levee erosion countermeasure site selection and design.

California↗
USGS2021

Process-based models and studies of coastal change to inform habitat restoration and climate change adaptation

Puget Sound salmon and estuary recovery strategies identify tens of thousands of acres of floodplain and estuary habitat restoration needed to re-establish ecosystem functions lost or degraded from western land use (Simenstad et al., 2011); the extent for nearshore habitat remains uncertain. Sediment is critical for shaping the structure and functions of these ecosystems and the success of many habitat recovery strategies. This is particularly important in the Pacific Northwest, where high sediment flux through the coastal zone makes it a more dynamic ecosystem driver than other regions where estuary restoration guidance has been developed and especially for extensive marshes and floodplains that have subsided due to lost sediment delivery from placement of flow control (flood protection) structures (Grossman et al., 2020). Fluvial sediment delivery to Puget Sound is expected to greatly increase in many systems under projected climate change (Lee et al., 2016), requiring better models and tools to evaluate complex ecosystem responses. Guidance for estuary habitat recovery (e.g., Clancy et al., 2009) rests on a paradigm of restoring historic habitats and connectivity by simply removing or lowering levees assuming sediment delivery and accumulation will occur. Outcomes of several restoration projects and studies show that restoring “opportunity” for sediment delivery may not be enough. Improved knowledge and predictive models of land-use and climate change effects on sediment budgets, sediment properties, and coastal change can refine restoration guidance to evaluate quantitative expectations for sediment flux, composition, accumulation, and timing critical to achieving more effective recovery, resilience, and community support.

Conference Paper↗
USGS1968

Chapter 9: Theory and processes relating to the lunar maria from the surveyor experiments

Prior to the Surveyor missions, there were three principal theories about the chemical constitution of the lunar maria: that the maria were (1) chondritic, (2) basaltic, or (3) silicic. Three types of materials recovered on Earth were suspected of coming from the maria: (1) chondritic meteorites, (2) basaltic achondrites, and (3) tektites. The Surveyor chemists have now spoken: Turkevich, Franzgrote, and Patterson find that, in Mare Tranquillitatis (ref. 9-1) and Sinus Medii (see ch. 7 of this report), the composition is basaltic. It is unmistakably too poor in magnesium to be like either kind of chondritic meteorite. It is too rich in the heavier elements, iron and calcium, to resemble terrestrial silicic rocks (the granitic kindred) or tektites.

Book chapter↗
USGS1967

Chapter 8: Lunar theory and processes

Significant new information has been provided by Surveyor III's successful landing and operation on the lunar surface; some of the most significant and interesting events are presented here. Pending completion of data reduction and more detailed analysis of the information available from the Surveyor mission, only limited interpretive discussion is included.

Book chapter↗
USGS1967

Chapter VIII: Lunar theory and processes

Much valuable new information has been provided by Surveyor III ; some of the most significant and interesting events are presented here. Only a limited interpretive discussion is included at this time, pending completion of data reduction and more detailed analysis of information available from the Surveyor mission.

Book chapter↗
USGS1981

Digital processing techniques for small digital arrays (FLD data set)

The purpose of the Workshop on Luminescence Techniques was threefold: (1) to review the state-of-the-art capabilities of luminescence methods, (2) to consider a variety of concepts for the development of future luminescence sensor systems, and (3) to discuss appropriate research and development strategies for advancing the current state-of-the-art.

Conference Paper↗