21. After the discovery of radioactivity, radiometric dating methods were developed, starting in the 20th century. 22. Radiometric dating has shown that the earliest known stromatolites are over 3.4 billion years old.23. His primary field was radiometric dating , which was transforming the field of geology in the 1950s. 24. Radiometric dating measures the steady decay of radioactive elements in an object to determine its age.25. Three major tools are used to date the CRBG flows : stratigraphy, radiometric dating , and magnetostratigraphy. 26. Subsequent fieldwork, metamorphic studies and radiometric dating has refined their chronology but supported their original hypothesis. 27. The age of the impact structure is somewhat contentious, in the absence of any radiometric dating . 28. For older fossils or actual rocks, you use radiometric dating ( as I think it's called ). 29. Radiometric dates of 1883-1870 Ma are reported for mafic, ultramafic, carbonatite and lamprophyre intrusions within the Trough.30. This technique is known as radiometric dating .
