This data release provides saturated sediment temperatures from vertical temperature profilers, pressure head data from co-located pizometers, and estimates of 1D groundwater flux using a recursive-estimation framework to infer groundwater/surface-water exchange based on the collected temperature time-series (approximate 1,6,16,26cm depths, AlphaMachX vertical temperature profilers) from below the sediment/water interface. A heat-transport problem was formulated as a state-space model (SSM), in which the spatial derivatives in the convection/conduction equation are approximated using finite differences. The SSM is calibrated to estimate time-varying specific discharge using the Extended Kalman Filter (EKF) and Extended Rauch-Tung-Striebel Smoother (ERTSS) algorithms. These algorithms are described in McAliley et al., 2024 (https://doi.org/10.1029/2021WR030443) and relevant algorithm has been publicly released previously on ScienceBase (https://doi.org/10.5066/P99DBTKT). This data release contains 3 zipped folders, EKF_ERTSS_results.zip that contains EKF and ERTSS groundwater flux estimates, Temperature_observations.zip that contains raw observed temperature time series, and Pressure_data.zip that contains raw observations of pressure from piezometers adjacent to vertical temperature profilers. Additionally, water pressure transducers (Onset HOBO model U20L) were suspended at two depths within 2" steel pipes with 20cm screen drivepoints that were driven vertically into bed sediments adjacent to locations TX129 and TX132.

This data release contains field measurements of shallow sediment and seawater temperatures near the shoreline at Hen Cove, Pocasset, Massachusetts. The measurements were made on August 16, 2022 by the U.S. Geological Survey (USGS) to evaluate where groundwater/surface-water exchange was occurring at Hen Cove.

Groundwater discharge points to coastal waters can be identified and quantified using natural electrical and temperature data. In August 2022, U.S. Geological Survey (USGS) collected water-borne electromagnetic induction and temperature along selected transects within Hen Cove on Cape Cod, Massachusetts, following a spatial survey of bed sediment temperature. Handheld thermal infrared data were also collected to locate areas of focused terrestrial groundwater discharge based on characteristic cool temperatures of groundwater in late summer. Those initial datasets guided the installation of vertical bed sediment temperature profilers, water pressure loggers suspended in piezometers, and the collection of pore water samples. The individual datasets from this study are described in more detail under the Child Items of this data release, organized by data type.

The bulk electrical conductivity of the subsurface was indirectly measured with electromagnetic imaging (EMI) by using induced secondary electromagnetic signals generated by subsurface electrical conductors in response to transmitted electromagnetic energy (Zohdy and others, 1974). Electromagnetic induction data were collected using a DUALEM-421 (DualEM, Inc.) mounted on an inflatable stand-up paddle board about 15 centimeters above the water surface. The DUALEM-421 uses 3 transmitter-receiver coil spacings (4-, 2-, and 1-meters) and 2 orientations (vertical dipole, and horizontal dipole). Larger coil spacings interrogate a larger/deeper sampling volume than smaller coil separations. REFERENCE: U.S. Geological Survey, Techniques of Water-Resources Investigations, Book 2, Chapter D1, Zhody, A. A. R., Eaton , G. P., and Mabey, D. R. https://doi.org/10.3133/twri02D1

Scientists from the U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center conducted a seasonal collection of surficial sediments from Chincoteague Bay and Tom's Cove, located between Assateague Island and the Delmarva Peninsula in March/April 2014 (2014-301-FA) and October 2014 (2014-322-FA). The sampling efforts were part of a larger U.S. Geological Survey study to assess the effects of storm events on sediment distribution. The objective of this study was to characterize the sediments of Chincoteague Bay in order to create baseline conditions to incorporate with hydrodynamic and sediment transport models in order to evaluate pre- and post-storm (Hurricane Sandy) change. This report serves as an archive for sedimentological data derived from the surface sediment. Data are available for a seasonal comparison between March/April 2014 and October 2014. Downloadable data are available as Excel spreadsheets (sediment samples) and as JPEG files (maps). Additional files include: detailed results of sediment grain size analyses, and formal Federal Geographic Data Committee metadata (data downloads).

Scientists from the U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center conducted a seasonal collection of surficial sediments from Chincoteague Bay and Tom's Cove, located between Assateague Island and the Delmarva Peninsula in March/April 2014 (2014-301-FA) and October 2014 (2014-322-FA). The sampling efforts were part of a larger U.S. Geological Survey study to assess the effects of storm events on sediment distribution. The objective of this study was to characterize the sediments of Chincoteague Bay in order to create baseline conditions to incorporate with hydrodynamic and sediment transport models in order to evaluate pre- and post-storm (Hurricane Sandy) change. This report serves as an archive for sedimentological data derived from the surface sediment. Data are available for a seasonal comparison between March/April 2014 and October 2014. Downloadable data are available as Excel spreadsheets (sediment samples) and as JPEG files (maps). Additional files include: detailed results of sediment grain size analyses, and formal Federal Geographic Data Committee metadata (data downloads).

Short cores were collected on the continental rise off Georges Bank. The character of the sediments and measured bottom currents show that the Western Boundary Undercurrent is a significant factor in sediment transport and deposition along the east coast continental rise. Size data for the sand and mud fractions were estimated by the compilers by subtracting the percent carbonate (composed largely of sand-sized planktonic foraminifera) from the coarse fraction. Silt and clay were not differentiated; the fine fraction is reported as mud.

Hydrologic data were collected in the nearshore lake-bottom sediments of five lakes on western Cape Cod, Massachusetts: Ashumet (Falmouth), Long (Centerville), Santuit (Mashpee), Shubael (Barnstable), and Snake (Sandwich) Ponds. Water budgets of flow-through glacial kettle lakes are commonly dominated by groundwater flow into and surface-water seepage out of the lake, and inputs and losses from precipitation and evaporation are typically smaller. This data release presents water flux data collected from sites at the five lakes where lake water is seeping downward across the groundwater/surface-water interface into the groundwater system. Detailed characterization of water flux across the lake-bottom interface is critical to assessing the lake's influence on the groundwater system. The water fluxes were calculated for four of the lakes by using measurements of bottom-sediment temperature in shallow (less than 20 centimeters) vertical profiles and were measured directly at all five lakes by using seepage meters. Data were collected over four periods. Seepage meter measurements were made during August and September 2015. Temperature profile data were collected from July 27 to October 13, 2016; September 19 to October 11, 2017; and February 13 to February 23, 2018. The data are divided into four data sets (child items): (01) Temperature measurements from the vertical profiles, (02) calculated seepage rates from the temperature profiles, (03) measured seepage rates from the seepage meters and associated site information, and (04) average calculated seepage rates for each vertical temperature profile site and associated site information.

Temperature profile and pressure data were collected using moored buoy from the Atlantic Ocean from May 4, 1975 to December 18, 1975. Data were submitted by Massachusetts Institute of Technology; Department of Geology and Geophysics (MIT) with support from the IDOE/POLYMODE (International Decade of Ocean Exploration / combination of USSR POLYGON project). The physical properties are air pressure, air temperature, current meter, sea surface temperature, wind speed, water temperature, and irradiance-downwelling.

Temperature profile and pressure data were collected using moored buoy from the Atlantic Ocean from May 4, 1975 to December 18, 1975. Data were submitted by Massachusetts Institute of Technology; Department of Geology and Geophysics (MIT) with support from the IDOE/POLYMODE (International Decade of Ocean Exploration / combination of USSR POLYGON project). The physical properties are air pressure, air temperature, current meter, sea surface temperature, wind speed, water temperature, and irradiance-downwelling.