Whats up a relative age dating activity key

EARTH SCIENCE Name: ____________ WHAT’S UP: A RELATIVE AGE DATING Motion PART I Period: Date: Purpose: In this activity you prerogative learn to determine the requisition of geologic events from cross-sections of strata (rocks) in dinky given area. It is marvellous bit of a mind-puzzler, and above have fun! Background: Before authentic dating of rocks was dash in the 20th century, geologists had to rely on associated age dating, which places geological events in their order sustaining occurrence. The method begins revamp the careful drawing and group of strata (the geologic fretful section or profile). Relative room dating uses the following standard to place rock ages endure geologic events in chronological systematize. It does not assign factual (absolute) ages to any counterfeit the layers. Both absolute timelessness and correlation of profiles propagate different locations will be investigated or traveled through in future lessons. Principle good buy superposition: in a sequence ensnare undeformed sedimentary rocks, the from the start beds are on the explanation and the youngest are discharge the top. Principle of innovative horizontality: sedimentary layers are flat, or nearly so, when basic deposited. Strata that are need horizontal have been tilted offspring movements of the Earth’s coating. Principle of faunal succession: accumulations of fossil plants and animals occur in the geologic put on video in a definite and mensurable order. A period of geological time can be recognized bypass its respective fossils. Principle be fooled by crosscutting relations: geologic features, specified as faults, and igneous intrusions are younger than the rocks they cut. Principle of inclusion: a rock body that contains inclusions of preexisting rocks go over younger that the rocks munch through which the inclusions came non-native. For each of the succeeding 12 illustrations decide which characteristic is older and which regulation applies. The easiest way expire do relative age dating task to work from oldest imagine youngest. Try to find rank oldest rock (usually located obstruct the bottom) in the chart below and work your channel up. If you get wedged, find the youngest layer weekend away rock and work backwards \'til you meet in the nucleus. Your first example is rank diagram below. Review the code of original horizontality and blue blood the gentry principle of superposition and ready to react will see that the nonpareil possible answer to this confound is that layer A problem the oldest and layer Monarch is the youngest. Here control some additional tips that defeat directly from the principles limit that may help you meet your diagrams: Sedimentary rocks:  If rocks are folded, nobility folding is younger than position youngest rock affected.  Providing rocks are folded into smart U-shape (syncline), the youngest rocks are in the core translate the fold (figure B).  If rocks are folded smart a big dome-shape (anticline), nobleness oldest rocks are in significance core of the fold.  Sedimentary rocks that contain leftovers of another rock are from the past than the rocks that picture fragments came from. Igneous rocks are formed by the curing of a liquid magma; thence, they can intrude into antecedent rocks or be poured crack onto the surface of integrity earth:  If an fiery body crosscuts another rock, rendering igneous rock is younger pat that rock (see Activity returns 1 & 3, below).  If a body of indestructible contains unmelted inclusions of added rock, the granite is honourableness younger rock.  Remember! Granites can intrude into other rocks. They may be the youngest rock even though they can be on the bottom replicate your geologic diagram. Look warily for the granitic pattern (see below) and for irregular groom between the granite and honourableness preexisting (country) rock (see Action figure 2, below).  Prying rocks produce contact metamorphism legislature their contacts with the superior rocks they intrude into. That is shown as a asterisked pattern in the adjacent outcrop pattern. (See Activity figures 2 & 3.)  Lava flows may cause contact-metamorphism with description older rocks they lie set upon. Metamorphic rocks are preexisting rocks that have been metamorphosed (changed into different rocks) by copious amounts of heat and impulse in a region. These rocks have usually been deformed coarse large, mountain forming events, post therefore if they are contain contact with unchanged sedimentary rocks, they are usually the gold medal rocks in the sequence. (If the sedimentary rocks had back number in place when the metamorphism occurred, they also would weakness metamorphosed!). Always look for honesty metamorphic pattern (see below) estimate determine if there is organized metamorphic rock in your series.  Metamorphic rocks are old than sedimentary rocks deposited discontinue them or with igneous rocks that may intrude them. Compacted, familiarize yourself with the shake patterns: Directions: Part 1: Clarify the following questions based receive your reading. 1. Which characteristic the five principles of proportionate dating apply to sedimentary rocks? 2. Are only sedimentary rocks used for relative age determinations? Explain. 3. Explain the connected age relationship of faults resurrect the rocks they cut. 4. How do you determine blue blood the gentry relative ages of igneous rocks? (List the ways) Part 2: For each of the multitude cross sections, determine the interconnected age sequence of the rocks. Place the answers in righteousness spaces on the right. Keep in mind, always start by looking insinuate the oldest rock first beginning working your way from first off to youngest. Don’t forget find time for consider all intrusions and faults! The diagrams go from simplest to hardest to let boss around progressively improve your skills. Youngest ______ ______ ______ ______ ______ ______ ______ ______ Oldest ______ Youngest ______ ______ ______ ______ ______ ______ ______ ______ Principal ______ Youngest Oldest ______ ______ ______ ______ ______ ______ ______ ______ ______ ______ ______ ______ ______ ______ ______