5. New York Botanical Gardens and the Bronx Zoo
A trip to the New York Botanical Gardens and the Bronx Zoo can fill a weekend. In addition to the plants and animal exhibits there are numerous notable geologic features worthy of examination. Both parks charge admission and parking fees, however the botanical garden sometimes offers free admission on certain weekdays, and only charges a small fee to access the grounds. Special exhibits within the park charge an additional fee at each site. The zoo costs more, and can be particularly crowded on the weekends during the warmer months. The botanical gardens has limited parking that can become full especially during the spring flowering and during fall color seasons. Both parks are also accessible via the subway and Metro North.
The Bronx Zoo Park
Like the other parks in the city, Bronx Zoo Park landscape has been modified to take advantage of the glaciated terrain. Most of the erratics have been moved or utilized in the construction of the open-air animal staging areas. The grizzly bear site has a particularly large and scenic glacially polished and grooved outcrop strewn with glacial erratics; with the addition of the bears makes it an interesting photo stop (Figure 23). Just outside of the World of Darkness exhibit building is a large glacial erratic named the Rocking Stone. It consists of a granitic gneiss and schist similar to the glacially polished rock it is sitting on.
It is important to remember that all the rocks in the Bronx were at one time many miles below the earth surface, and that the rock masses we observe today are only remnants of great mountain ranges that formed in the region during Late Ordovician time, and continued to evolve during the Silurian and Devonian periods that followed. Most radiogenic dates derived from rocks in the New York City region record a date of Late Devonian time. This corresponds to the last significant stage of metamorphic thermal heating that the rocks in the New York City region experienced during the following Devonian Acadian Orogeny. Although Cameron's Line is mapped in the eastern portion of the Bronx, the great thrust faults associated with this continental suture probably moved oceanic crustal rocks far westward into New Jersey. Portions of the thrust sheet associated with Cameron's line may be present along the western edge of Manhattan and westward under portions of the Newark Basin region. Through the ages, the land has worn down as erosion stripped away these rocks. The resulting sediments were incorporated into sedimentary rock formations throughout the Appalachian Basin and into sediments beneath shallow seaways that existed during much of Paleozoic time across the Midcontinent and beyond. (The term, Appalachian Basin, refers to all of the sedimentary and igneous deposits that accumulated intermittently during the Paleozoic and Early Mesozoic along the eastern margin of North America. These materials now represent the extensive rock formations that have been faulted, folded and metamorphosed, and subsequently exposed by erosion throughout the extent of the Appalachian Mountains.)
The URL is: https://gotbooks.miracosta.edu/gonp/nyc/parks/loc5.htm
Last modified: 3/11/2019