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Open the “Angel Lake, Nevada” folder. Check the “Angel Lake, NV” placemark to fly there. What carved this valley?Tip: Consider its shape

Turn on the “Deserts Overlay”. What kind of desert produced this dune field?Tip: Use the overlay to determine which desert it is part of then decide what kind of desert it is. 

Zircons contain a radioactive isotope called Uranium-238 which has a half life of 4.5 billion years (Ga). How old are these minerals?Tip: 4.5 Ga*how many half lives(don’t round up/down)=age in Ga (*100 to get age in million years ago (Ma))

We can extract zircons, a radioactive mineral, from sample Y to obtain a time since the minerals formed- thereby providing the numeric age of this layer.Within the zircons in this rock sample, the ratio of parent to daughter isotopes is 15.5:0.5. Using the chart below, determine how many half lives have passed.

At the top of the sequence you find a rock (sample 7) that bubbles when in contact with acid. Inspect sample 7 further:

Inspect the following image (the red line illustrates the location of the equator). Is this an accurate representation of the planet’s historical supercontinent? (consult the relevant maps-think about Alfred Wegener’s evidences for continental drift)

This is a satellite image of the volcano on which sample 3 was collected. Along the flank of this volcano, we see several puzzling circular features (see image below). What are these?

At the base of the sequence you find a rock (sample 9). It feels like sandpaper against your fingers. Inspect sample 9 further:

Sample 6 is found in a layer featuring pink granite dikes, overlain by a clastic sediment layer. At the boundary between the two layers, there is an unconformity (red line). What kind of unconformity is it?  

According to what you know about samples 7-9, which are true of the landscape at this location over time? (Mark all that apply. Think about where the oldest vs youngest rock layer is in the sequence.)