what is observed through geochemical technique?
These observations may help to deduce the global level of biological activity at a certain period, or the affinity of certain fossils.
Paleontology
Geochemical observations may help to deduce the global level of biological activity at a certain period, or the affinity of certain fossils. 
match the type of play with the age of occurrence UNANSWERABLE what is paleontology? The scientific study of life that existed prior to, and sometimes including, the start of the Holocene Epoch. how is the study done? It includes the study of fossils to classify organisms and study interactions with each other and their environments. what are the other branches of science related to it? Biology and geology.
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Paleontology [SEP] Geochemical observations
Geochemical observations may help to deduce the global level of biological activity at a certain period, or the affinity of certain fossils. For example, geochemical features of rocks may reveal when life first arose on Earth, and may provide evidence of the presence of eukaryotic cells, the type from which all multicellular organisms are built. Analyses of carbon isotope ratios may help to explain major transitions such as the Permian–Triassic extinction event.