Dean Simon M 2004 (Table T3) Potassium oxide, uranium and thorium concentration in ODP Site 195-1201 sediments dataset https://doi.org/10.1594/PANGAEA.779130 Dean Simon M 2004 Analysis of NGR spectra from deep-sea sediments in the Philippine Sea, Site 1201 book chapter In: Shinohara, M; Salisbury, MH; Richter, C (eds.) Proceedings of the Ocean Drilling Program, Scientific Results, College Station, TX (Ocean Drilling Program) 195 https://doi.org/10.2973/odp.proc.sr.195.105.2004 1-33 Natural gamma ray measurements are made routinely during core logging using the physical property multisensor track. The instrument provides a measure of the natural decay of radioactive elements in the core, expressed in counts per second, which is generally used as a proxy for the clay content of nonmarginal marine sediments. At Site 1201 spikes of increased gamma ray emissions, up to six times the average for the entire core over depth intervals on the order of 20-50 cm, are observed from the sediments within 50 m of the basement contact. The spikes show a strong correlation with sediment color variations, coinciding with red/brown layers within otherwise green/gray-colored sediments. In this paper, the gamma ray spectra obtained from 21 measurements using a 4-hr counting period are analyzed to obtain the absolute concentration of the radioactive elements K2O, U, and Th in both the intervals with spikes and the intervals with relatively low count rates. In addition, the concentration of these elements is estimated using the spectra obtained from the routine 20-s counting period measurements and which, although exhibiting a great deal of scatter due to the high statistical uncertainty in the original measurements, are roughly similar to those obtained from the 4-hr counting period. Baseline concentrations for U (1 ppm) and Th (5 ppm) match published averages for the amount present in deep-sea clays; the peak concentrations measured correspond to an additional concentration of 100%-200%. The results are compared to those from downhole logging and shipboard inductively coupled plasma-atomic emission spectrometry measurements. The gamma ray spectra results do not support postdepositional fluid flow through the sediment as the source of the enrichment of radioactive elements. It is more likely that the spikes in the gamma ray emissions are simply the result of interbedding sediments from two different sources, one with relatively high concentrations of K2O, U, and Th. 135.09915 135.09915 19.2977166666666 19.2977166666666 135.09915 19.2977166666666 2001-03-31T00:00:00 2001-04-25T00:00:00 460.41 513.46 ODP Ocean Drilling Program https://www-odp.tamu.edu:443/ Ocean Drilling Program, Texas A&M University ODP http://www-odp.tamu.edu/ https://ror.org/01f5ytq51 195-1201 19.297716666667 135.09915 Philippine Sea -5709.7 2001-03-31T00:00:00 2001-04-25T00:00:00 Leg195 Leg195 2001-03-05T00:00:00 2001-03-05 2001-05-03T00:00:00 2001-05-03 Joides Resolution https://www-odp.tamu.edu:443/resolutn.html Salisbury, Matthew H Salisbury, Matthew H Shinohara, Masanao Shinohara, Masanao doi:10.2973/odp.proc.ir.195.2002 Joides Resolution https://www-odp.tamu.edu:443/resolutn.html Composite Core COMPCORE 1320 m 523.7 m 73 cores; 659.6 m cored; 621.3 m drilled; 79.4% recovery 63 CC-BY-3.0 Creative Commons Attribution 3.0 Unported https://creativecommons.org/licenses/by/3.0/ DEPTH, sediment/rock Depth sed m depth http://purl.obolibrary.org/obo/PATO_0001595 sediment http://purl.obolibrary.org/obo/ENVO_00002007 rock Length L http://dbpedia.org/resource/Length Depth sed [m] Potassium oxide K2O % potassium oxide http://purl.obolibrary.org/obo/CHEBI_88321 Dimensionless Ratio ψ Natural gamma-ray spectroscopy tool (NGT) Dean Simon M K2O [%] Uranium U mg/kg uranium Natural gamma-ray spectroscopy tool (NGT) Dean Simon M U [mg/kg] Thorium Th mg/kg thorium http://purl.obolibrary.org/obo/CHEBI_33385 Natural gamma-ray spectroscopy tool (NGT) Dean Simon M Th [mg/kg] supplement citable author41172 basis5 campaign21707 campaign3383798 event2075176 geocode1 geocode1599 geocode1600 geocode1601 geocode8128 inst34 license101 method10895 method91 param1546 param701 param811 pi41172 project3 ref36136 term1073131 term1073193 term20641 term2632269 term38263 term40550 term41056 term43794 term43863