Create accountLogin

Recent searches

No recent searches

Search options

Only available when logged in.
dmv.community is one of the many independent Mastodon servers you can use to participate in the fediverse.
A small regional Mastodon instance for those in the DC, Maryland, and Virginia areas. Local news, commentary, and conversation.

Administered by:

Server stats:

155
active users

dmv.community: AboutStatusProfiles directoryPrivacy policy

Mastodon: AboutGet the appKeyboard shortcutsView source codev4.3.7

#unconformity

0 posts0 participants0 posts today
Public *
Vicky Veritas

The Great Unconformity

Left to right on top of my notebook are:
Tapeats Sandstone deposited 525 million years ago in a beach environment.
Zoraster Granite emplaced 1.7 billion years ago.
Vishnu Schist 1.8 billion years ago.

Both of the bottom layers are the roots of mountains that eroded away.

Right where my foot is, the contact between the Tapeats and the Zoraster, there is over a BILLION years missing in the rock record called an unconformity. It was named the Great Unconformity by John Wesley Powell, and yes, you need to capitalize it.

These rocks can be seen at Frenchman's Stop in the Frenchman Mountains outside of Las Vegas, and also at the bottom of the Grand Canyon.

Picture of 3 rocks on top of a notebook. From left to right is the Tapeats Sandstone, the Zoraster Granite, and the Vishnu Schist.
Picture of the Tapeats Sandstone lying next to the Zoraster Granite. My boot toe is touching the contact between the two, which is know as the Great Unconformity.
#geology#unconformity#TheGreatUnconformity
ExploreLive feeds
About