Causes of T-Wave Abnormality on an EKG. Abnormal T-Waves on an EKG aren't necessarily an indicator of a problem. However, they could cause your doctor to want to do further testing. The heart has its independent electrical systemâ a network of nerves located throughout all its chambers, which mediate electrical impulses that enable chambers to contract in a synchronized rhythm and sequence.
Chronometric definition, a timepiece or timing device with a special mechanism for ensuring and adjusting its accuracy, for use in determining longitude at sea or for any purpose where very exact measurement of time is required. See more.
1 This technique measures the ratio of two lead isotopes (lead-206 and lead-207) to the amount of uranium in a mineral or rock. 2  Often applied to the trace mineral zircon in igneous rocks, this method is one of the two most commonly used (along with argon-argon dating) for geologic dating.eochronology is the science of determining the age of rocks, fossils, and sediments using signatures inherent in the rocks themselves. Absolute geochronology can be accomplished through radioactive isotopes, whereas relative geochronology is provided by tools such as palaeomagnetism and stable isotope ratios.