| The lavas have been divided into two main series based on their stratigraphy, geochemistry and petrography. |
| His subsequent findings demonstrated the value of petrography, the descriptive branch of the study of rocks. |
| Thus from mineralogy and petrography it contains information regarding the origin and subsequent mutations of minerals and rocks. |
| The field-based studies were supplemented by thin-section petrography and whole-rock geochemistry to characterize different intrusive phases. |
| In addition, detailed thin section petrography provided better understand mineralogical and diagenetic controls on porosity and permeability. |
| The radiometric age data combined with the petrography of the volcanics thus indicate two separate events of volcanism in the Danish North Sea. |
