TPL texas pacific land corporation NYSE Oil & Gas Production TTI tetra technologies, inc. NYSE Oil & Gas Production TUSK mammoth energy services, inc. NASDAQ Oilfield Services/Equipment USEG u.s. energy corp. NASDAQ Oil & Gas Production VET vermilion energy inc. common (canada) NYSE Oil & Gas Production VLO valero energy corporation NYSE Integrated oil Companies VNOM viper energy, inc. - class a NASDAQ Oil & Gas Production VOC voc energy trust units of beneficial interest NYSE Oil & Gas Production VTNR vertex energy, inc NASDAQ Integrated oil Companies WPRT westport fuel systems inc - common shares NASDAQ Industrial Machinery/Components WRD weride inc. - american depositary shares NYSE Oil & Gas Production WTI w&t offshore, inc. NYSE Oil & Gas Production WTTR select energy services, inc. class a NYSE Oilfield Services/Equipment WWD woodward, inc. NASDAQ Industrial Machinery/Components XOM exxon mobil corporation NYSE Integrated oil Companies YPF ypf sociedad anonima NYSE Integrated oil Companies