Ways of Measuring Absolute Time Tree rings- every year a tree grows a new ring.When the tree dies, the rings can be counted and events such as forest fires can be dated.
Brchatting with naked women - Relative age dating worksheet
Erosion wears away the uppermost layers Area submerges and deposition begins again. The almost vertical layers on the bottom formed first.
They tilted a little then eroded to make the straight cutoff (the diagonal line going from bottom left to top right).
Then the final deposit was the layers to the top left.
The law of cross-cutting relationships: anything that cuts across layers of rock is younger than the rocks that it has intruded into. Vocabulary Sequence Puzzles: Sequence 1 Sequence 2 Sequence 3 Sequences 1, 2 & 3 on one sheet Sequence 4 Sequence 5 Sequence 6 Sequence 7 Relative Dating Craters (see PPT to the right for answers) Worksheet on Radio Dating DBQ on Dinosaurs DBQ on The Natural History of LI DBQ on Magnetic Pole Reversals All three layers of rock (limestone, sandstone, shale) were made, then the volcano formed.
The fuzzy line is contact metamorphism where the hot magma "fried" the surrounding rock and changing it to metamorphic rock (ex. This image shows an igneous intrusion cutting through sedimentary layers.
A closer examination (not possible from this picture) would reveal contact metamorphism where the intruding igneouos rock "cooked" the pre-existing sedimentary layers.
Formation of an Unconformity Layers are formed according to superposition.
Photo by Phil Medina Volcanic time markers - a layer of volcanic dust covering layers.
When a violent eruption of a volcano occurs it may send dust high into the atmosphere where it can spread over the entire planet.
It settles out of the air and forms a layer over wide regions at the same time. The remians of the impact site in Mexico as seen by satellite imagery.
Example: the layer that marks the extinction of dinosaurs has characteristics of an asteroid impact.