Attribute_Accuracy_Report:
Laboratory analyses conducted at USGS Woods Hole Coastal and Marine Science Center Sediment Laboratory using Ohaus AX224 micro-balance with listed readability of 0.0001 grams, and repeatablity of +or- 0.0001 grams. Difference between first and second weighing were checked for stability and were within +or- 1%.
Water samples were collected using a van Dorn sampler, and processed for suspended-sediment concentration(SSC) following USGS methods (Fishman and Friedman, 1989). Water samples were stored in a refrigerated and dark location, and were filtered within one month of collection. The entire volume of each water sample was filtered to avoid sub-sampling errors. Deionized water was put through each filter as the last step of the filtration process to rinse dissolved salts from the filter. Standard laboratory protocols (Fishman and Friedman, 1989) were followed to ensure thorough drying and accurate weighing of samples.
Horizontal_Positional_Accuracy:
Horizontal_Positional_Accuracy_Report:
Horizontal position was determined using a Garmin GPSMAP 78sc handheld GPS. The expected absolute, horizontal accuracy is stated to be 3 to 5 m at the 95% confidence level using the WAAS setting. Additional sources of error in the position for the water sample locations are caused by the offset from the GPS and the exact location of the van Dorn water sampler at the time the sample was taken, which could be as large as 2 m; therefore overall expected accuracy of the reported horizontal position for these water sample locations is on the order of 7 m or better. One exception is sample 160 where no GPS way point was stored and the horizontal position coordinates were estimated from the samples taken before and after at the GB4 site location; for this sample the position accuracy could be greater than 7 m.
Vertical_Positional_Accuracy:
Vertical_Positional_Accuracy_Report:
Total water column depth values at each sample site were determined from using a handheld depth sounder. Sample depths were determined by markings on the lowering line for the van Dorn sampler, and the samples were typically between 0.25 and 0.75 m above the seabed. Depths given were taken from the water surface at time of sample, and were not referenced to a fixed datum. Expected accuracy of depth measurements is 0.3 m or better.
Process_Step:
Process_Description:
Deployment sample collection: Collect 99 water samples using van Dorn water sampler at deployed instrument sites (17 samples) and other locations (72 samples) in Grand Bay from 20160802 - 20160807.
Process_Date: 201608
Process_Step:
Process_Description:
Filter water samples (80 of 99 collected) at the Grand Bay National Estuarine Research Reserve using 47mm, 1.5 micron pore size, pre-weighed, pre-volatilized 934-AH glass fiber filters. Entire sample volume was filtered. If necessary samples were split between 2 or more filters if solids load was too much for a single filter. Water samples were resuspended in bottle prior to pouring into filter funnel. A final rinse was made using deionized water to wash out dissolved salts from each filter.
Process_Date: 201608
Process_Step:
Process_Description:
Determine suspended-sediment concentration (SSC) in grams per liter using "Solids, residue at 105 C, suspended, gravimetric" method from Fishman and Friedman (1989). Laboratory analyses conducted at USGS Woods Hole Coastal and Marine Science Center Sediment Laboratory using Ohaus AX224 micro-balance.
Process_Date: 201608
Process_Step:
Process_Description:
First servicing sample collection: Collect 42 water samples using van Dorn water sampler at deployed instrument sites (13 samples) and other locations (29 samples) in Grand Bay from 20161019 - 20161024. This was during the first turnaround where deployed instruments were recovered, downloaded, cleaned, and batteries and anti-fouling controls refreshed as necessary. Nineteen of the samples were collected at the end of the first deployment (A) period and the remaining 23 after the instruments were serviced and re-deployed for the beginning of the second deployment (B).
Process_Date: 201610
Process_Step:
Process_Description:
Filter water samples at the Grand Bay National Estuarine Research Reserve using 47mm, 1.5 micron pore size, pre-weighed, pre-volatilized 934-AH glass fiber filters. Entire sample volume was filtered. If necessary samples were split between 2 or more filters if solids load was too much for a single filter. Water samples were resuspended in bottle prior to pouring into filter funnel. A final rinse was made using deionized water to wash out dissolved salts from each filter.
Process_Date: 201610
Process_Step:
Process_Description:
Determine suspended-sediment concentration (SSC) in grams per liter using "Solids, residue at 105 C, suspended, gravimetric" method from Fishman and Friedman (1989). Laboratory analyses conducted at USGS Woods Hole Coastal and Marine Science Center Sediment Laboratory using Ohaus AX224 micro-balance.
Process_Date: 201611
Process_Step:
Process_Description:
Recovery sample collection: Collect 46 water samples using van Dorn water sampler at deployed instrument sites (31 samples) prior to final instrument recovery, and at other locations within Grand Bay (15 samples) from 20170123 - 20170128.
Process_Date: 201701
Process_Step:
Process_Description:
Filter water samples at the Grand Bay National Estuarine Research Reserve using 47mm, 1.5 micron pore size, pre-weighed, pre-volatilized 934-AH glass fiber filters. Entire sample volume was filtered. If necessary samples were split between 2 or more filters if solids load was too much for a single filter. Water samples were resuspended in bottle prior to pouring into filter funnel. A final rinse was made using deionized water to wash out dissolved salts from each filter.
Process_Date: 201701
Process_Step:
Process_Description:
Determine suspended-sediment concentration (SSC) in grams per liter using "Solids, residue at 105 C, suspended, gravimetric" method from Fishman and Friedman (1989). Laboratory analyses conducted at USGS Woods Hole Coastal and Marine Science Center Sediment Laboratory using Ohaus AX224 micro-balance.
Process_Date: 201703
Process_Step:
Process_Description:
Use Microsoft Excel to compile all laboratory analysis of suspended-sediment concentration (SSC) from collected water samples. Add sample locations (latitude/longitude) to the compiled tabular results spreadsheet. Export results spreadsheet to comma-separated values (csv) file format.
Process_Date: 201910
Process_Step:
Process_Description:
Added keywords section with USGS persistent identifier as theme keyword.
Process_Date: 20200806
Process_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: U.S. Geological Survey
Contact_Person: VeeAnn A. Cross
Contact_Position: Marine Geologist
Contact_Address:
Address_Type: Mailing and Physical
Address: 384 Woods Hole Road
City: Woods Hole
State_or_Province: MA
Postal_Code: 02543-1598
Contact_Voice_Telephone: 508-548-8700 x2251
Contact_Facsimile_Telephone: 508-457-2310
Contact_Electronic_Mail_Address: vatnipp@usgs.gov
