shale

It is a former manufacturing state that has been transitioning to newer industries and businesses, but it has a large energy sector because of its abundant oil shale deposits.

At one point, Harris was asked about the liberal positions, such as those on oil shale fracking, that she took during her failed 2019 presidential campaign and has since abandoned.

But, in the clips released so far, Ms Harris did not explain her reversal on banning fracking - a technique for recovering gas and oil from shale rock used by an industry that is particularly strong in the battleground state of Pennsylvania.

Does she think it’s more necessary to keep the Democratic coalition fired up heading into the convention and beyond, or to signal to swing voters that she’s ready to smash some shale rock to smithereens and huff up its delectable hydrocarbons?

The researchers found that, even years later, the tissue and shells of mussels contained radium that could be traced to wastewater from fracking in the Marcellus Shale.