Gas sand

{
  "id": "MLC-T-OAG-004344",
  "term": "Gas sand",
  "field": "Oil and gas",
  "definition": "A porous and permeable sandstone whose pore space holds natural gas beneath an impermeable cap rock. On well logs it shows high resistivity and low bulk density, while the neutron porosity reads low, so the neutron and density porosity curves cross over. That crossover, called gas effect, separates a gas sand from an oil or water sand of similar porosity.",
  "subject": "Geology",
  "url": "https://mlchart.com/terminology/oil-and-gas/gas-sand/"
}