Ground-based transient electromagnetic data and resistivity models at selected sites of the California Central Coast and San Joaquin Valley 2019
Dates
Publication Date
2022-08-10
Start Date
2019-05-30
End Date
2019-06-05
Citation
Bloss, B.R., Ball, LB., and Groover, K.D., 2022, Ground-based transient electromagnetic data and resistivity models at selected sites of the California Central Coast and San Joaquin Valley 2019: U.S. Geological Survey data release, https://doi.org/10.5066/P908GEV7.
Summary
Ground-based transient electromagnetic (TEM) data were acquired by the U.S. Geological Survey (USGS) at 16 locations of California’s southwestern San Joaquin Valley and Central Coast regions to define the electrical resistivity structure of hydrogeologic materials. Data were acquired using the ABEM WalkTEM system (Guideline Geo Ab, Sundbyberg, Sweden). TEM data were processed and numerically inverted to derive one-dimensional resistivity structure using SPIA (Aarhus Geosoftware, Aarhus, Denmark). The resulting models reveal vertical variations in electrical resistivity associated with geologic structure and zones of high salinity groundwater. This release includes raw and processed TEM data and a resistivity model for each data location [...]
Summary
Ground-based transient electromagnetic (TEM) data were acquired by the U.S. Geological Survey (USGS) at 16 locations of California’s southwestern San Joaquin Valley and Central Coast regions to define the electrical resistivity structure of hydrogeologic materials. Data were acquired using the ABEM WalkTEM system (Guideline Geo Ab, Sundbyberg, Sweden). TEM data were processed and numerically inverted to derive one-dimensional resistivity structure using SPIA (Aarhus Geosoftware, Aarhus, Denmark). The resulting models reveal vertical variations in electrical resistivity associated with geologic structure and zones of high salinity groundwater.
This release includes raw and processed TEM data and a resistivity model for each data location using the following structure:
├── COGG_TEM_data_models_2019.xml
├── COGG_TEM_2019_SoundingLocationsModels.gdb.zip - file geodatabase with all models and plots attached. This is a mirror of the contents of the model directory.
└── COGG_TEM_data_models_2019.zip
├── Data
│ ├── COGG_Raw_Data (USF Files)
│ │ ├── USF_format_description_508.pdf - manual describing the USF file format
│ │ ├── COGG_SoundingID-USF_lookup.csv - lookup table linking USF file to Sounding ID. Also includes information on WalkTEM channel mapping for moment and receiver types
│ │ └── USF files (16 files) - raw, unprocessed data files with naming convention [LONGDATE] + [_TIMESTAMP] + [_STATIONID].usf, where LONGDATE (ex.20160621), TIMESTAMP (ex. 230145_828), STATIONID (ex. Station1)
│ └── COGG_Processed_Data (TEM Files)
│ ├── AarhusInv_manual_TEM.txt - manual describing the TEM file format
│ └── TEM files (64 files) - processed data files with naming convention [COGG_TEM] + [_DATE] + [_SURVEY] + [_STATION] + [_MOMENT] + [-RECEIVER].tem, where DATE (ex. 180224), Survey (ex. LH), STATION (ex. 01a), MOMENT (ex. LM), RECEIVER (ex. RC005)
├── Models
│ ├── COGG_Model_Plots
│ │ └── Image files of model plots (16 files) - Images of model plots with naming convention [COGG_TEM] + [_DATE] + [_SURVEY] + [_STATION].png, where DATE (ex. 180224), SURVEY (ex. LH), STATION (ex. 01a)
│ ├── TEM_model_data_dictionary.csv - Data dictionary describing all channels in tabulated model file
│ └── COGG_TEM_models.csv - tabulated model file. All channels are described in the model data dictionary
└── COGG_TEM_2019_Locations.gdb.zip - file-geodatabase containing all sounding locations, model information, and has the model plots linked to each site. The TEM_model_data_dictionary.csv file also applies to the attribute table of this file geodatabase
Click on title to download individual files attached to this item.
COGG_TEM_data_models_2019.xml Original FGDC Metadata
View
27.73 KB
application/fgdc+xml
COGG_TEM_data_models_2019.zip
5.47 MB
application/zip
Purpose
These data were collected in support of groundwater salinity mapping and hydrogeologic framework development as part of the California State Water Resources Control Boards Oil and Gas Regional Monitoring Program and the U.S. Geological Survey California Oil, Gas, and Groundwater Program.
