Short-lived radioisotope (SLRad) data collected aboard R/V Justo Sierra cruise JS-0815 in the southern Gulf of Mexico from 2015-07-31 to 2015-08-08

This dataset contains short-lived radioisotope (SLRad) data collected aboard R/V Justo Sierra cruise JS-0815 in the southern Gulf of Mexico from 2015-07-31 to 2015-08-08. SLRad data were generated for selected core sub-samples at 2mm sampling intervals for “surficial unit” and 5mm sampling resolution intervals to the base of cores. SLRad data generated include sample activity as disintegrations per minute per gram (dpm/g) of 1) Excess Thorium-234 (234Thxs) activity, which is calculated by measuring the total Thorium-234 (234ThTot) activity and the subtraction of the measured or estimated “supported” Thorium-234 (234ThSup) activity, 2) Excess Lead-210 (210Pbxs) activity, which is calculated by measuring the total Lead-210 (210PbTot) activity and subtraction of the measured background "supported" Lead-210 (210PbSup) activity {average of Lead-214 (214Pb) at 295 kiloelectron volts (keV), 214Pb at 351keV, and Bismuth-214 (214Bi) at 609keV}, 3) Cesium-137 (137Cs) activity, and 4) Berilium-7 (7Be) activity. The cruise documentation was provided for the R/V Justo Sierra cruise JS-0815. The cruise was led by chief scientist Dr. David Hollander.

本数据集收录了2015年7月31日至2015年8月8日期间，在墨西哥湾南部由R/V Justo Sierra号科考船执行JS-0815航次时采集的短寿命放射性同位素（short-lived radioisotope, SLRad）数据。针对选定的岩芯子样本，表层单元（"surficial unit"）采用2毫米采样间隔进行数据采集，岩芯至底部段则以5毫米采样分辨率开展采样。本次生成的SLRad数据涵盖四类核素的比活度，单位为每分钟衰变数每克（disintegrations per minute per gram, dpm/g）：1. 过剩钍-234（Excess Thorium-234, ²³⁴Thxs）活度，通过测定总钍-234（total Thorium-234, ²³⁴ThTot）活度，并减去实测或估算的支撑态钍-234（supported Thorium-234, ²³⁴ThSup）活度计算得到；2. 过剩铅-210（Excess Lead-210, ²¹⁰Pbxs）活度，通过测定总铅-210（total Lead-210, ²¹⁰PbTot）活度，并减去实测背景下的支撑态铅-210（supported Lead-210, ²¹⁰PbSup）活度计算得到，其中支撑态铅-210活度取295千电子伏（kiloelectron volts, keV）处的铅-214（Lead-214, ²¹⁴Pb）、351千电子伏处的铅-214，以及609千电子伏处的铋-214（Bismuth-214, ²¹⁴Bi）活度的平均值；3. 铯-137（Cesium-137, ¹³⁷Cs）活度；4. 铍-7（Beryllium-7, ⁷Be）活度。本数据集配套提供了R/V Justo Sierra号JS-0815航次的科考文档，本次航次由首席科学家戴维·霍兰德（Dr. David Hollander）博士主持。