| Gravity cores from San Pablo Bay and Carquinez Strait, San Francisco Bay, California |
gravitycore |
"This data release contains information on gravity cores that were collected by the U.S. Geological Survey in the area of San Pablo Bay and Carquinez Strait, California in 1990, 1991, and 2000. Ten (10) pdf files describe gravity cores that were split, photographed, and imaged by X-rays, and another pdf file contains a core-log legend. In addition, a shapefile provides sample collection data.
Seventy-two gravity cores were collected by the U.S. Geological Survey in 1990, 1991, and 2000 from San Pablo Bay and Carquinez Strait, California. Gravity cores from San Pablo Bay contain bioturbated laminated silts and sandy clays, whole and broken bivalve shells (mostly mussels), fossil tube structures, and fine plant or wood fragments. Gravity cores from the channel wall of Carquinez Strait east of San Pablo Bay consist of sand and clay layers, whole and broken bivalve shells (less than in San Pablo Bay), trace fossil tubes, and minute fragments of plant material." |
Don Woodrow |
| Analysis for estimated percent sand in cores taken from San Francisco Bay, California, 1990-2016 |
gravitycore |
Sediment analysis of cores collected in San Francisco Bay, San Pablo Bay, and the Carquinez Strait and Suisun Bay, California from 1990 to 2016 for percent sand. Handwritten core logs, x-radiographs, and the cores themselves, were examined for the presence of sand. |
Theresa Fregoso |
| 10 cm intervals of percent sand content for 186 sediment cores collected in San Francisco Bay, CA, 1990-2016 |
gravitycore |
Percentage of sand content provided in 10 cm intervals down the length of 186 sediment cores collected in San Francisco Bay, California in 1990-91, 2000, 2006, and 2016. Sediment data were obtained from a combination of gravity, box, and push cores ranging in length from 14 to 360 cm. Sand content percentages were obtained from a compilation of visual analyses, descriptive and graphical core logs, and grain size measurements. For the purposes of modeling variability in sand content with depth beneath the San Francisco Bay floor, percent sand content values were converted from variable layer thicknesses based upon natural breaks within the core, to regularly spaced 10-cm intervals using a weighted average. |
Theresa Fregoso |
