18. geologic time quiz study guide...chapter 12 section 1 relative dating an unconformity is a break...
TRANSCRIPT
Geologic Time Test Study Guide
1. Whatisthedifferencebetweenuniformitarianismandcatastrophism?
2. Whatisrelativedating?
3. Whatisthelawofsuperposition?
Uniformitarianism: thesamegeologicprocessesshapingtheEarthtodayhavebeenatworkthroughoutEarth’shistory
Chapter 12 Section 1The Earth’s Story and Those Who First Listened
Catastrophism:aprinciplethatstatesthatgeologicchangeoccurssuddenly
Determiningwhetheranobjectoreventisolderoryoungerthanotherobjectsorevents
Theprinciplethatstatesthatyoungerrockslieaboveolderrocksinundisturbedsequences
4. Whatistheprincipleoforiginalhorizontality?
5.Whatisanunconformity?Whatcausesunconformities?
Chapter 12 Section 1Relative Dating
Anunconformityisabreakinthegeologicrecordcreatedwhenrocklayersare erodedorwhensedimentisnotdepositedforalongperiodoftime
Sedimentisgenerallydepositedinflat,horizontallayers.Ifitistiltedandbent,thenitoccurredaftertherocklayersformedinflat,horizontallayers
Unconformity
What is an unconformity?
Layer(s) of missing rock, due to erosion or nondeposition.
6.Whatisafossil?
7. Inwhattypeofrockaremostfossilsfound?
8.Whatisatracefossil?
9.Whatisanindexfossil?
Tracesorimprintsoflivingthingsthatarepreservedinrock
Anynaturallypreservedevidenceofanimalactivity(coprolite)
Chapter 12 Section 2Evidence of the Past
SedimentaryRock
Fossilsoforganismsthatlivedduringarelativelyshort,well-definedgeologictimespan(trilobites)
10.Whatarethe2conditionsthatfavorpreservationofanorganismasafossil?
11.Howcanfossilshelpbuilddetailedpicturesofpastenvironments?
Chapter 12 Section 2Evidence of the Past
1. RapidBurial– protectsanorganismfrombeingeatenordecomposing
2. PossessionofHardParts– theyaremorelikelytoremainintactlongenoughtobecomefossilized
1. Fossilizedclamshells:theremusthavebeenanoceanthere
2. Fossilizedcoral:theremusthavebeenashallowtropicalseathere
3. Coal:Theremusthavebeenaswampwithtropicalplants
12. Whatisradioactivedecay?
13. Whatisabsolutedating?
14.Whatisthemostcommonmethodofabsolutedating?
15.Whatishalf-life?
16.Whatisanisotope?
Anymethodofmeasuringtheageofaneventorobjectinyears
Radiometricdating
Chapter 12 Section 3Absolute Dating: A Measure of Time
Thetimeneededforhalfofasampleofaradioactivesubstancetobecomestable
Anatomthathasthesamenumberofprotonsasotheratomsofthatelementbutadifferentnumberofneutrons(andthereforeadifferentatomicmass)
Theprocessofunstablenucleibecomingstablebyspontaneouslybreakingapartandreleasingenergy
17.Whatisradiometricdating?
18.Whycan’tradiometricdatingbeusedtodatesedimentaryrock?Howdogeologistsgettheageofitthen?
Chapter 12 Section 3Absolute Dating: A Measure of Time
Amethodofdeterminingtheageofanobjectbyestimatingtherelativepercentagesofaradioactive(parent)isotopeandastable(daughter)isotope
SedimentinrocksareweatheredfromsomanydifferentrocksofdifferentagesTheymustrelatethesedimentaryrocktodatablemassesofigneousrock
19. Howoldistheearth?
20. WhatdogeologistscalltheperiodoftimebeforetheCambrianperiod?
21. Beabletoplacetheerasinthecorrectorderfromoldesttomostrecent.
22.Howlongagodidthedinosaursbecomeextinct?
Chapter 12 Section 4Eras of the Geologic Time Scale
PaleozoicàMesozoicà Cenozoic
4.6Billion-ish yearsold
Pre-Cambriantime
65millionyearsago
23.Whicherameans“Ancientlife”becausegeologiststhoughtthiswastheoldestrockthatexisted?Listsomebasicfactsfromthisera.
24.Whicherawasthe“AgeoftheReptiles”?Listsomebasicfactsfromthisera.
25.Whicherawasthe“AgeoftheMammals”?Listsomebasicfactsfromthisera.
CenozoicEra
Chapter 12 Section 4Eras of the Geologic Time Scale
MesozoicEra
PaleozoicEra -- dominatedbyfish,Amphibians,EarlyReptiles,Landplantsemerge
-- Earlybirdsappear,firstflowingplants,dinosaursdominant
-- Mammals,primates,andhumans