l>keolistravelservices.comLOGY and keolistravelservices.comGRAPHY that THE brand-new YORK BIGHT

THE HIGHLANDS REGION

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An outcrop that granite gneiss over a billion year old rises abovethe woodedhillsides in Harriman State Park. Barren ourcrops such as thesedisplay abundantglacial striations indigenous the keolistravelservices.comlogically "very recent" ice cream agesof the PleistoceneEpoch.The Highland region encompasses the upland locations of north NewJersey, the Hudson Highlands region of southern brand-new York(including Manhattan, the Bronx, and parts the Brooklyn and StatenIsland), and upland components of Connecticut. The region is arugged, hilly to mountainous terrain, bearing the charactericscars ofPleistocene glaciation. The rocky outcrops visible on hillsidesand follow me stream banks consist greatly of old gneiss andschist (highly metamorphosed sedimentary and igneous rocks) thatwere once hidden many miles below the earth"s surface. The figurebelow is a keolistravelservices.comlogic map the generally incorporates the HighlandsRegion within the greater brand-new York Bight area. Rocks ofPrecambrian, Cambrian, Ordovician, and Silurian periods arerepresented.
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(Image produced with Portrait USA CD-ROM v permission bythe American keolistravelservices.comlogical Institute.)Current expertise is that the age of the planet is around 4.6billion year old, through the oldest known rocks on Earth"s surfacedated at around 3.8billion years. The oldest rocks in the brand-new York Bight region arefound insurface outcrops transparent the Highlands region. Theseexposures of Precambrian "basement rock" have been estimated at 1.3 come 1.1billion year old.These rocks underlie younger rocks throughout much of the area,and haveundergone a high degree of change since their formation. Theearly stagesof change occurred in a mountain-building illustration that impacted the entire eastern margin of phibìc America. Thismountain-building episode is jointly known as the GrenvilleOrogeny i m sorry ended around a billion year ago. Throughout thisperiod enlarge rocks and also sediments were subjected to deep burialand metamorphic alteration. A long period of uplift and erosion complied with the GrenvilleOrogeny; yet later on periods the mountain-building regarded theformation that the Appalachian Mountains additionally contributed to thealteration and tectonic deformation of these rocks. Beginningroughly 700 million years earlier rifting began along the easternedge of the north American continent. The rifting led to theformation the the old Iapetus Ocean, a waterway that has sincevanished by later on collisions in between continents (via processesassociated with plate tectonics). Two "smaller" mountain-building episodes arisen in earlyPaleozoic time: The Taconic Orogeny and also the Acadian Orogeny. The Taconic Orogeny began in Cambrian time (about 480 millionyears ago) and ended around Late Ordovician time (about 440million year ago). Throughout the Taconic Orogeny a small landmass,similar in dimension to modern-day Japan, was accreted ~ above the NorthAmerican continent in the southern brand-new England. Beforeand during this orogeny, sedimentary deposits formed on themargins the both the north American continent, and also within anintervening deep naval basin. Today, these sedimentary rocksform the core ofthe Taconic hills (east that the Hudson River, normally northof the TappanZee Bridge). Similar to most mountain-building illustration vulcanismoccurred all at once with tectonism. Igneous intrusionsoccurredthroughout the new England region. Heat and also pressure associatedwith deep burial and tectonic deformation converted sedimentaryand igneous rocks to metamorphic rocks (marble, quartzite,phyllite, schist, and gneiss). A 2nd event, the Acadian Orogeny, started in early on Devoniantime (about 410 million year ago) and also ended in ~ the beginning ofMississippian time (about 350 million years ago). This orogenyis additionally associated with the collision and also accretion of a smallerlandmass (the Avalon Terrane) in the northern brand-new England region,however, tectonic deformation connected with this event(particularly faulting and folding) impacted much of the entireNew York Bight region. A last mountain structure episode, calledtha Appalachian Orogeny, began about 310 million years ago, andwas the an outcome of continent collision between North America andAfrica. This led to partial development of the supercontinentPangaea. The Appalachian Orogeny (or Alleghany Orogeny) isresponsible for the formation of the folded and also faulted mountainbelt that extends native southern new York southward into Alabamaand beyond. The orogeny ended throughout the Permian period (about250 million years ago). The Appalachian mountain building eventcreated a large mountain selection and additional deformed andmetamorphosed rocks previously changed by earlier mountainbuilding episodes. The figure listed below is a generalized graphicsummary of how the the three episodes developed in relationship toplate tectonic theory.
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After Pangaea created an extensive period of erosion complied with asthe suppercontinent continued to evolve. Start in Triassictime Pangaea began to be traction apart, beginning a phase ofrifting, sedimentation, and volcanism.A short summary as presented over does not carry out justice come a halfa billion years of earth history! added information followson the Catskills and also following keolistravelservices.comlogy net pages.

FIELD TRIPS

The Highlands region can be a hold to a wide range of keolistravelservices.comlogyfield tripdestinations. Of specific note encompass the famous iron andzinc mines andmuseums that the Franklin and also Ogdensburg,NJarea.


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An additional popular long walking area in the Highlands an ar of NewJersey thatdisplays abundant keolistravelservices.comlogic features is the PyramidMountain area near Boonton, NJ. Terrific hikes in theHighlands region ofNew York incorporate the an extremely popular Harriman State Park (the imageshown above)and Bear mountain State Park.
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