Performance of Earth Retention System, St. Louis Data Center

The design and performance of the earth retention system for a 35 ft deep excavation in medium clay is described. The earth retention system consisted of soldier piles and lagging with tieback anchors. One level of tiebacks included helical anchors installed in loose to medium dense sand. Behavior of the helical anchors in contrast to conventional drilled-in anchors is discussed

Constrained nearshore larval distributions and thermal stratification

© The Author(s), 2018. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Marine Ecology Progress Series 595 (2018): 105-122, doi:10.3354/meps12561.Vertical and cross-shore distributions and abundances of shallow-water barnacle larvae were characterized in La Jolla, southern California (USA), during a 2 yr period. Five stations located within 1 km of shore and ranging from 4-12 m water depths were sampled intensively in 2 m depth intervals during 27 cruises throughout spring-summer (April-July) and fall-winter (October-December) of 2014 and 2015. Larval abundances significantly decreased from 2014 to 2015, which could be related to the arrival of a warm-water anomaly (the so-called ‘Blob’) in 2014 and El Niño conditions in 2015. Despite the presence of these large-scale regional disturbances, vertical and cross-shore larval distributions were consistent throughout the 2 yr study period. Early-stage nauplii and Chthamalus fissus cyprids tracked bottom depth, and cyprids were on average deeper than nauplii. Vertical distributions were not related to the mid-depth of the thermocline or thermal stratification. Early-stage nauplii had a broader cross-shore distribution than cyprids, which were concentrated at inshore stations. Nearshore cyprid concentration had a positive relationship with thermal stratification, and the center of distribution of cyprids was farther offshore during fall-winter when stratification decreased. These results suggest that thermal stratification elicits enhanced behavioral control of cyprids to remain close to shore and reach the adult habitat.This material is based upon work supported by the National Science Foundation under grants OCE-1357290, OCE-1357327, OCE-1630459, and OCE- 1630474. Support was also provided by the University of San Diego and Woods Hole Oceanographic Institution

Department of the Interior (DOI) Reorganization of Ocean Energy Programs

This report looks at recent Department of the Interior (DOI) institutional reforms and use of its new regulatory framework. These changes are meant to facilitate ocean energy development that was mandated by the Outer Continental Shelf Lands Act (OCSLA)

Outer Continental Shelf Moratoria on Oil and Gas Development

Moratoria measures for the outer continental shelf (OCS) establish bans or restrictions on oil and gas exploration and development in federal ocean areas. With some exceptions for marine sanctuaries and monuments, no portion of the federal OCS has a permanent moratorium on oil and gas leasing and development. While some areas are under temporary development bans, such as suspensions or moratoria directed by either legislative or executive powers, most of the OCS is free of such restrictions and is considered permissible for offshore leasing activity

Outer Continental Shelf Moratoria on Oil and Gas Development

This report discusses moratoria measures for the outer continental shelf (OCS) which establish bans or restrictions on oil and gas exploration and development in federal ocean areas. It includes a background of offshore oil and gas development, the sources of U.S. moratorium policy, the background of ocean governance, U.S. moratoria in international areas, and related issues for congress

Diversity and distribution of nearshore barnacle cyprids in southern California through the 2015-16 El Nino

© The Author(s), 2019. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Hagerty, M. L., Reyns, N., Pineda, J., & Govindarajan, A. F. Diversity and distribution of nearshore barnacle cyprids in southern California through the 2015-16 El Nino. Peerj, 7, (2019): e7186, doi: 10.7717/peerj.7186.Abundance, species diversity, and horizontal distributions of barnacle cyprids offshore of La Jolla, southern California were described from May 2014 to August 2016 to determine how the nearshore barnacle larval assemblage changed before, during, and after the 2015–16 El Niño. The entire water column was sampled at five stations located within one km of shore with water depths of 4, 6, 8, 10, and 12 m during 33 cruises that encompassed the time when El Niño conditions impacted the area. Nearshore temperature and thermal stratification was concurrently measured using a CTD. Six identified cyprid species, including Chthamalus fissus, Pollicipes polymerus, Megabalanus rosa, Tetraclita rubescens, Balanus glandula, and B. trigonus, along with four unknown species, were collected in our samples. DNA barcoding was used to confirm identifications in a subset of the larvae. C. fissus was more than eight times more abundant than any other species, and while abundance varied by species, cyprid density was highest for all species except for M. rosa before and after the El Niño event, and lower during the environmental disturbance. There were significant differences in cross-shore distributions among cyprid species, with some located farther offshore than others, along with variability in cross-shore distributions by season. C. fissus cyprids were closest to shore during spring-summer cruises when waters were the most thermally stratified, which supports previous findings that C. fissus cyprids are constrained nearshore when thermal stratification is high. Relative species proportions varied throughout the study, but there was no obvious change in species assemblage or richness associated with El Niño. We speculate that barnacle cyprid species diversity did not increase at our study site during the 2015–16 El Niño, as it has in other areas during previous El Niño Southern Oscillation events, due to the lack of anomalous northward flow throughout the 2015–16 event.Funding for this project was provided by the National Science Foundation under grants OCE-1357290, OCE-1357327, OCE-1630459, and OCE-1630474, with supplemental funding provided by the University of San Diego and Woods Hole Oceanographic Institution. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

The Pilot Lunar Geologic Mapping Project: Summary Results and Recommendations from the Copernicus Quadrangle

The first systematic lunar geologic maps were completed at 1:1M scale for the lunar near side during the 1960s using telescopic and Lunar Orbiter (LO) photographs [1-3]. The program under which these maps were completed established precedents for map base, scale, projection, and boundaries in order to avoid widely discrepant products. A variety of geologic maps were subsequently produced for various purposes, including 1:5M scale global maps [4-9] and large scale maps of high scientific interest (including the Apollo landing sites) [10]. Since that time, lunar science has benefitted from an abundance of surface information, including high resolution images and diverse compositional data sets, which have yielded a host of topical planetary investigations. The existing suite of lunar geologic maps and topical studies provide exceptional context in which to unravel the geologic history of the Moon. However, there has been no systematic approach to lunar geologic mapping since the flight of post-Apollo scientific orbiters. Geologic maps provide a spatial and temporal framework wherein observations can be reliably benchmarked and compared. As such, a lack of a systematic mapping program means that modern (post- Apollo) data sets, their scientific ramifications, and the lunar scientists who investigate these data, are all marginalized in regard to geologic mapping. Marginalization weakens the overall understanding of the geologic evolution of the Moon and unnecessarily partitions lunar research. To bridge these deficiencies, we began a pilot geologic mapping project in 2005 as a means to assess the interest, relevance, and technical methods required for a renewed lunar geologic mapping program [11]. Herein, we provide a summary of the pilot geologic mapping project, which focused on the geologic materials and stratigraphic relationships within the Copernicus quadrangle (0-30degN, 0-45degW)

Deepwater Horizon Oil Spill: Highlighted Actions and Issues

This report highlights actions taken and issues raised after the April 20, 2010 explosion on the Deepwater Horizon offshore drilling rig and the resulting oil spill in the Gulf of Mexico