Geology of New Yorkand New JerseyJ Bret Bennington and Charles MerguerianHofstra University
View of the tiltedand eroded edge ofthe Palisades intru-sive sheet in NewJersey as seen fromInwood Hill Park onthe east bank ofthe Hudson River,New York City.
New YorkNew Jersey
Over one-and-a-half billion years of geologic history are recorded in the landformsand rocks found within 100 kilometers of New York City, revealing multiple episodesof plate collision and orogeny, continental rifting, volcanism, and an ever-changingtableau of environments from tropical seas to glaciated landscapes. This bookletexplains the geologic events that have shaped the eastern continental margin ofNorth America, and also discusses the economic resources and geohazards of theNew YorkNew Jersey metropolitan region.
Coverage extends from western Connecticut to southern New Jersey and spans theAtlantic Coastal Plain westward across the metamorphic Piedmont provinces, NewarkBasin, Proterozoic Highlands, Appalachian Fold Belt, and Paleozoic Plateau regions.
Written to illustrate basic concepts of plate tectonics and rock formation presented inintroductory geology and physical geography courses, the Geology of New York andNew Jersey is appropriate for courses aimed at both majors and non-majors wherediscussion of the geologic history of the northeast will make the course content moreregionally relevant for the students. Incorporate this content with any Thomson EarthScience text, including Physical Geology: Exploring the Earth, 6th edition, by Monroe,Wicander and Hazlett. To learn more please visit: www.thomsonedu.com/earthscience.
Also AvailablePeople often decide on their residence or business location based on a desire to liveor work in scenic environments without understanding the hazards around them.Thus, a series of reprinted chapters from Donald and David Hyndmans NaturalHazards and Disasters has been carefully selected to provide students with theopportunity to see how specific natural hazards are relevant to their regional area.
Each volume has been reprinted in its entirety, including end-of-chapter problemsand Case In Point case studies, for easy integration into a variety of introductorycourses where discussion of natural hazards can add relevant context to the regularcoursework.
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Physiographic diagram showing the major geological provinces in southeastern New York, northern New Jersey, and adjoining states.Numbers correspond to figure numbers in the text and show approximate geographic locations of photos.
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ESSENTIAL QUESTIONS TO ASKNew YorkNew Jersey.1 Introduction
What duration of time and what geological eras are recorded in rocks of the New YorkNew Jersey region?
What are the names of convergent orogenic events that took place during this time interval?
New YorkNew Jersey.2 Ancient Roots of the Grenville Orogeny The Grenville Orogeny was part of the assembly of a Proterozoic supercontinent. What is
the name of the supercontinent? Name five places within 100 miles of New York City where geologists and students can
study rocks of the Grenville Orogeny.
New YorkNew Jersey.3 Carbonate Seas and the Taconic Orogeny What types of sedimentary layers were deposited during the opening of the Iapetus Ocean,
before the start of the Taconic Orogeny? Identify at least five rock types formed during the Taconic Orogeny. Which geological province contains the metamorphic roots of the ancient Taconic
Mountains? Which geological province preserves the sediments eroded off of the risingTaconic Mountains?
New YorkNew Jersey.4 Assembly of a Supercontinent The assembly of supercontinent Pangaea took roughly 250 million years and involved a
collision between North America and what two other landmasses? What tectonic environment and what life-forms existed during deposition of the
Helderberg Group of formations in the Early Devonian Period? After the deposition of the Helderberg limestones, what change took place in the sediments
being deposited in the New YorkNew Jersey region and to what tectonic event can they beattributed?
New YorkNew Jersey.5 Breakup of Pangaea During early Mesozoic time, the split up of Pangaea resulted in the formation of elongate
rift basins along the eastern margin of North America. Name a place on Earth todaywhere modern rift valleys are forming.
In the New YorkNew JerseyConnecticut region, name three Mesozoic basins and thetypical rock types you might find in them.
New YorkNew Jersey.6 Creation of the Atlantic Coastal Plain Creation of the Atlantic Coastal Plain mirrors conditions that existed in eastern North
America at other times in the past. Name at least two earlier intervals of time whenpassive margin conditions existed along the coast of North America.
What ages and types of sediments are common in coastal plain strata, and what kinds offossils are found in them?
New YorkNew Jersey.7 Ice Age Landscapes Global cooling and the formation of glaciers took place during the Pleistocene Epoch.
Name three features each of glacial erosion and glacial deposition found in the New YorkNew Jersey region.
Glacial deposits have produced major landforms and topographic features in the New YorkNew Jersey area. Name at least three examples of these.
New YorkNew Jersey.8 Economic Mineral Resources Name a dozen economic mineral resources that have been mined for hundreds of years in
the New YorkNew JerseyConnecticut region. The Franklin Furnace District of northwestern New Jersey has been a rich source of metals.
Name the main ore minerals from this area and the metals that are extracted from them.
New YorkNew Jersey.9 Geological Hazards of the Region Name three types of geological hazards associated with the New YorkNew Jersey area. Why are moderate earthquakes, which cause little damage in West Coast cities such as
Los Angeles, such a potential danger for East Coast cities such as New York and Newark?
2007 Thomson Brooks/Cole, a part of the Thomson Corporation. Thomson, the Star logo, and Brooks/Cole are trademarks used hereinunder license. ALL RIGHTS RESERVED. No part of this work covered by the copyright hereon may be reproduced or used in any form or byany meansgraphic, electronic, or mechanical, including photocopying, recording, taping, Web distribution or information storage andretrieval systemswithout the written permission of the publisher. The Adaptable Courseware Program consists of products and additions toexisting Brooks/Cole products that are produced from camera-ready copy. Peer review, class testing, and accuracy are primarily the responsibilityof the author(s). The Geology of New York Tri-State Area /Charles Merguerian and J Bret Bennington - First Edition ISBN 0-759-39063-0.Printed in the United States of America.
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New YorkNew Jersey.1IntroductionVolcanoes, high mountains, earthquakes, and other indicatorsof active geological upheaval are currently associated with thewestern United States. By contrast, the eastern margin of thecontinent seems relatively quiet, but this was not always thecase. The New YorkNew Jersey metropolitan region lies onthe edge of the North American continent and has experi-enced a long history of geological activity as eastern NorthAmerica collided with other tectonic plates and then riftedapart again. The products of these tectonic interactionsgeological structures and rock formationsare exposed inthe landscape beneath our feet. Geologists reconstruct thehistory of the Earth by mapping, collecting, and analyzing therocks, minerals, fossils, and geological structures preserved indifferent geological provinces. What is remarkable aboutNew York and New Jersey is that, within a 100-kilometer(60-mile) radius of New York City, eight major geologicalprovinces are present (Figure NY-NJ.1) that display morethan 1 billion years of geological history (Figure NY-NJ.2).The remnants of tropical seas, volcanic eruptions, deepmagma intrusion, rising mountains, shifting faults, andadvancing glaciers are all on display and ready to be appreci-ated by anyone with a basic knowledge of geology and a littleimagination. This chapter reviews the geological featuresthat are found in the New YorkNew Jersey metropolitanregion and relates the geological features of the present land-scape to the events that formed them in the past. We also dis-cuss the economic benefits, as well as the hazards, affordedby the geology of this region.
All rocks have a story to tell. One of the greatest scientificachievements of the twentieth century was the discoverythat there is a unifying theme to the stories found in rocksthe theory of plate tectonics. The lithosphere of the Earthis broken up into discrete plates that are created at mid-ocean ridges and move across the surface of the planet untilthey are consumed along deep ocean trenches. Because ofplate tectonics, continents and ocean basins are not staticfeatures of the Earth; rather, they are constantly m