Editing Thomas Gold (section)

===The helium anomaly===

In later publications, Gold emphasized that the immense amounts of [[helium]] gas that surges upward during commercial petroleum production at some sites is proof in itself that substantial lightweight gases have indeed persisted at depth since the amalgamation of cosmic debris into planet Earth during the birth of this solar system. In his 1998 book, Gold closed his fourth chapter, "Evidence for Deep-Earth Gas," with a section titled "The Association of Helium with Hydrocarbons."<ref name="DHB-1998">{{cite book |last1=Gold |first1=Thomas |title=The Deep Hot Biosphere |date=1998 |publisher=Springer-Science |location=New York |isbn=978-0-387-95253-6}}</ref>