GEO 401 Test 1 exam 2023 with 100% correct answers

Radiocarbon is formed in ____________________. - correct answer -The upper atmosphere by N14 reacting with radiation. What climate variable might "clumped isotopes" measure? - correct answer -Temperature What are "clumped" isotopes? - correct answer -A temperature dependent affinity for heavy isotopes boned to other heavy isotopes. 100% universal, pure temperature proxy. Calculate temp within a degree. Split second reorganization of the crystal as it pops into the lattice. Temperature dependent. Example: C13-O18 Which location might you expect the delta18O value of water to deviate most form typical ocean values? - correct answer -Cold, deep ocean waters. At what depths do foraminifera live? - correct answer -All depths How long can a coral colony live? - correct answer -Centuries How can we measure the age of a coral colony? - correct answer -Band counting, uranium series dating, new coral growing on top of old coral. How old is the oldest ice on Earth? - correct answer -2.7 million years old What causes varves in high altitude? - correct answer -Lakes form ice over which cuts off sediment input. When ice breaks, surge of sediment goes into lake, producing layers of sediments. What can cause bands in ice cores? - correct answer -Different seasons (summer and winter). Winter is darker layers.