id	keyword
esrj-34799	et al
esrj-34799	maturity
esrj-34799	coal
esrj-34799	volume
esrj-34799	extracts
esrj-34799	source
esrj-34799	oils
esrj-34799	shale
esrj-34799	table
esrj-34799	basin
esrj-34799	anambra
esrj-34799	radke
esrj-34799	petroleum
esrj-34799	rock
esrj-34799	hydrocarbons