The multiple choice with regards to problem A picture. 4) Igneous intrusion \"Y\
ID: 288473 • Letter: T
Question
The multiple choice with regards to problem A picture.4) Igneous intrusion "Y" is found cutting across X, A and B forming an igneous rock body called a-7(0.5 pt) a) batholith b) pluton d) dike Given: Intrusion X contains radioactive isotopes with a known half-life of 83,000,000 years. How many half-live have elapsed, if for every 50% parent isotope 50% daughter isotopes are found? (0.5 pt) a) 1 half lives b) 3 half lives c)2 half lives d) 4 half lives a) 249 million years b) 83 million years )332 million years d) 166 million years a) Mesozoic, Cretaceous b) Mesozoic Jurassic ) Paleozoic, Carbo 6) What is the age of Intrusion X? (0.5pt) 7 In which geologic time (Era and Period) was intrusion X formed? (Refer to Geologic Time Scale on page 360 your lecture text.) (0.5 pt) b) Mesozoic, Jurassic c)Paleozoic, Carboniferous d) Mesozoic, Triassic Problem B Cross Section: (total 9.5 points)
Explanation / Answer
Complete order of events 1. Intrusion of X into unknown rock (older) 2. Intrusion Y 3. Ocean rise or land subsides and deposition off units A B C D E forming UC1 4. Uplift tilting and erosion of units A B C D and Y 5. Uplift and erosion of unknown rock type exposing igneous unit X 6. Oceans rise or land subsides deposition if F Z forming unconformity UC 2 7. Uplift and erosion of F and Z forming moden day surface (Younger). Answers from question 1 to 7 find below 1. Intrusion X us older; principle of cross cutting relationship 2. Angular unconformity 3. Disconfomity 4. Dike 5. 3 half lives 6. 83 million years 7. Paleozoic, Carboniferous