rock oil

But by fracking the rock, oil flowed from the shale.

From The Wall Street Journal ● Apr. 8, 2014

There are likewise springs of rock oil or bitumen.

From A General History and Collection of Voyages and Travels — Volume 02 Arranged in Systematic Order: Forming a Complete History of the Origin and Progress of Navigation, Discovery, and Commerce, by Sea and Land, from the Earliest Ages to the Present Time by Robert Kerr

Then came the great discovery of rock oil, which rapidly superseded the whale oil of commerce in general use.

From Equatorial America Descriptive of a Visit to St. Thomas, Martinique, Barbadoes, and the Principal Capitals of South America by Maturin Murray Ballou

Girl in Tranquilla convent that nun told me liked to smell rock oil.

From Ulysses by James Joyce

His words are:— “Petroleum, rock oil, or what the Welsh call it, Ymenin tylwyth têg, or Fairies’ butter, has been found in the lime stone strata in our mineral country. 

From Welsh Folk-Lore a Collection of the Folk-Tales and Legends of North Wales by Elias Owen