0d4002bb-8ca1-4d5f-ba87-91dfd5a281d5

Evolution of the Grand Portage National Monument Landscape.

Block diagram schematic illustration of the evolution of the Grand Portage landscape. Block A shows an ancient subduction zone dipping beneath Archean mountains with map unit PRrv being deposited in the back arc basin. Block B shows crustal extension of the basin and rifting with volcanic and sedimentary material being deposited in the rift basin. Block C shows streams and rivers eroding into the deposited sediments during a time of tectonic quiescence.

Schematic graphics illustrating the evolution of the Grand Portage National Monument landscape. Not to scale.

Permission must be secured from the individual copyright owners to reproduce any copyrighted materials contained within this website. Digital assets without any copyright restrictions are public domain.

Graphics by Trista L. Thornberry-Ehrlich (Colorado State University).

Public domain:Full Granting Rights

Image

Grand Portage National Monument, Code: GRPO

Grand Portage National Monument, Cook County, Minnesota
Latitude: 47.999698638916, Longitude: -89.7606964111328

NPS.gov Collection

01/01/0001

Public Can View

Tuesday, July 6, 2021 5:58:30 PM

Tuesday, July 6, 2021 5:58:30 PM

Figure_4_ac_geologic_evolution-01.jpg

Monday, January 1, 0001 12:00:00 AM

jpg

1.4 MB

Scenic