The 1, 850-year-old Penokean magmatism in Wisconsin represents margin-type igneous activity terminated by collision.
12.
Most geologists now accept the theory that the older rocks at the center of the uplift are a result of this deep seated igneous activity.
13.
Mesozoic igneous activity is largely responsible for this diversity of mineral deposits and the mineral concentrations have been variably enhanced by hydrothermal activity associated with faulting.
14.
The Saint Francois Mountains were formed by igneous activity, whereas most of the surrounding Ozarks are developed on Paleozoic sedimentary rocks as a dissected plateau.
15.
In the Cenozoic Era, which extended from 66 million years ago to present day, igneous activity was renewed in the eastern part of the State.
16.
The HALIP is widely thought to have originated from a mantle plume, and the igneous activity of the province often tracked along a similar path as the Icelandic hotspot.
17.
A hypothesis states that the Jackson Volcano and related igneous activity in Mississippi were a result of the superplumes, similar to the conditions that created the Deccan Traps and the Siberian Traps.
18.
Minor but significant igneous activity occurred during the Mesozoic era, including kimberlite emplacement during the Jurassic period, and the development of alkalic intrusions along the Ottawa-Bonnechere Graben and elsewhere in Ontario.
19.
While a few intrusive igneous formations found as far south as Mexico City are dated to the Late-Jurassic or Early Cretaceous, the Gulf of Mexico during that time was relatively void of igneous activity.
20.
The Newark sediments are extremely thick ( up to 6 kilometers ); they were deposited in a series of half-grabens that were themselves igneous activity; a superb example is the New Jersey Palisades sill.
