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Geographic data related to Geology of Connecticut at OpenStreetMap - Connecticut Geology, Wesleyan University
As part of New England, Connecticut has undergone much geologic change shaped by plate tectonics, volcanism, and glacial activity.
During the early Triassic period, the super-continent Pangea was formed as the Iapetus Ocean closed up and the proto-North American continent collided with Avalonia, part of modern-day Africa. This caused great uplift and the creation of the Appalachian Mountains, which, at the time, were bigger than modern-day Himalayas. Erosion of the Appalachian Mountains now exposes metamorphic rocks once very deep in the Earth's mantle and uplifted during this time period.
About 200 million years after this collision and the formation of Pangea, during the middle of the Mesozoic Era, the Atlantic Ocean floor started spreading and great extensional forces were experienced, resulting in faulting. Connecticut's Eastern border fault was created, a fault which begins in New Haven and stretches 130 miles up to Keene, New Hampshire. As a result, the land west of this fault was downset, creating a rift valley and causing the land to tilt an average of 15 to 25 degrees. The fault is currently inactive. The formation of this basin eventually refilled with soft fluvial and alluvial sediments.
During Ice Ages, glacial activity shaped much of New England’s landscape, eroding mountains, leaving glacial till scattered everywhere, and forming glacial lakes. At its greatest extent, one of these glaciers left behind a moraine which became today's Long Island. One of the biggest glacial lakes of the time was Glacial Lake Hitchcock. It formed when the Laurentide Ice Sheet retreated and glacial meltwater began to accumulate at the glacier's terminal moraine in Rocky Hill, Connecticut and back up into the Connecticut River. The glacial lake left behind a soft, varved landscape, gathering silt and sand in the summertime due to the influx of glacial meltwater and clay in the wintertime as the lake froze until it was later drained drained.
This soft surface has since been downcut, resedimented and oft flooded by the Connecticut River, making it a very soft, nutrient-replenished area and host to the majority of Connecticut's farmland soils. The land on either side of the Connecticut River Valley is less suitable for farmlands. The eastern section holds the shallow Proto-North American Terrane while the western section contains the Iapetos and Avalonian Terranes, which still holds remnants of glacial till and lack the soft fluvial sediments so prominent in the Connecticut River Valley region.
Geographic data related to Geology of Connecticut at OpenStreetMap 
A glacier is a persistent body of dense ice that is constantly moving under its own weight. A glacier forms where the accumulation of snow exceeds its ablation over many years, often centuries. It acquires distinguishing features, such as crevasses and seracs, as it slowly flows and deforms under stresses induced by its weight. As it moves, it abrades rock and debris from its substrate to create landforms such as cirques, moraines, or fjords. Although a glacier may flow into a body of water, it forms only on land and is distinct from the much thinner sea ice and lake ice that form on the surface of bodies of water.
Landforms are categorized by characteristic physical attributes such as their creating process, shape, elevation, slope, orientation, rock exposure, and soil type.
The exposed geology of the Yosemite area includes primarily granitic rocks with some older metamorphic rock. The first rocks were laid down in Precambrian times, when the area around Yosemite National Park was on the edge of a very young North American continent. The sediment that formed the area first settled in the waters of a shallow sea, and compressive forces from a subduction zone in the mid-Paleozoic fused the seabed rocks and sediments, appending them to the continent. Heat generated from the subduction created island arcs of volcanoes that were also thrust into the area of the park. In time, the igneous and sedimentary rocks of the area were later heavily metamorphosed.
The Interior Plains is a vast physiographic region that spreads across the Laurentian craton of central North America, extending along the east flank of the Rocky Mountains from the Gulf Coast region to the Arctic Beaufort Sea. In Canada, it encompasses the Canadian Prairies separating the Canadian Rockies from the Canadian Shield, as well as the Boreal Plains and Taiga Plains east of the Mackenzie and Richardson Mountains; while in the United States, it includes the Great Plains of the West/Midwest and the tallgrass prairie region to the south of the Great Lakes extending east to the Appalachian Plateau region.
Glacial landforms are landforms created by the action of glaciers. Most of today's glacial landforms were created by the movement of large ice sheets during the Quaternary glaciations. Some areas, like Fennoscandia and the southern Andes, have extensive occurrences of glacial landforms; other areas, such as the Sahara, display rare and very old fossil glacial landforms.
Lake Hitchcock was a glacial lake that formed approximately 15,000 years ago in the late Pleistocene epoch. After the Laurentide Ice Sheet retreated, glacial ice melt accumulated at the terminal moraine and blocked up the Connecticut River, creating the long, narrow lake. The lake existed for approximately 3,000 years, after which a combination of erosion and continuing geological changes likely caused it to drain. At its longest, Lake Hitchcock stretched from the moraine dam at present-day Rocky Hill, Connecticut, to St. Johnsbury, Vermont. Although the rift valley through which the river flows above Rocky Hill actually continues south to New Haven, on Long Island Sound, the obstructing moraine at Rocky Hill diverted the river southeast to its present mouth at Old Saybrook.
The Oak Ridges Moraine is a geological landform that runs east-west across south central Ontario, Canada. It developed about 12,000 years ago, during the Wisconsin glaciation in North America. A complex ridge of sedimentary material, the moraine is known to have partially developed under water. The Niagara Escarpment played a key role in forming the moraine in that it acted as a dam for glacial meltwater trapped between it and two ice lobes.
A terminal moraine, also called end moraine, is a type of moraine that forms at the terminal (edge) of a glacier, marking its maximum advance. At this point, debris that has accumulated by plucking and abrasion, has been pushed by the front edge of the ice, is driven no further and instead is deposited in an unsorted pile of sediment. Because the glacier acts very much like a conveyor belt, the longer it stays in one place, the greater the amount of material that will be deposited. The moraine is left as the marking point of the terminal extent of the ice.
The glacial history of Minnesota is most defined since the onset of the last glacial period, which ended some 10,000 years ago. Within the last million years, most of the Midwestern United States and much of Canada were covered at one time or another with an ice sheet. This continental glacier had a profound effect on the surface features of the area over which it moved. Vast quantities of rock and soil were scraped from the glacial centers to its margins by slowly moving ice and redeposited as drift or till. Much of this drift was dumped into old preglacial river valleys, while some of it was heaped into belts of hills at the margin of the glacier. The chief result of glaciation has been the modification of the preglacial topography by the deposition of drift over the countryside. However, continental glaciers possess great power of erosion and may actually modify the preglacial land surface by scouring and abrading rather than by the deposition of the drift.
The Geology of Pennsylvania consists of six distinct physiographic provinces, three of which are subdivided into different sections. Each province has its own economic advantages and geologic hazards and plays an important role in shaping everyday life in the state. From the southeast corner to the northwest corner of the state, the include: the Atlantic Plain Province province, the Piedmont Province, the New England Province, the Ridge and Valley Province, the Appalachain Province, and the Central Lowlands Province.
New Jersey is a very geologically and geographically diverse region in the United States' Middle Atlantic region, offering variety from the Appalachian Mountains and the Highlands in the state's northwest, to the Atlantic Coastal Plain region that encompasses both the Pine Barrens and the Jersey Shore. The state's geological features have impacted the course of settlement, development, commerce and industry over the past four centuries.
Fluvioglacial landforms are those that result from the associated erosion and deposition of sediments caused by glacial meltwater. These landforms may also be referred to as glaciofluvial in nature. Glaciers contain suspended sediment loads, much of which is initially picked up from the underlying landmass. Landforms are shaped by glacial erosion through processes such as glacial quarrying, abrasion, and meltwater. Glacial meltwater contributes to the erosion of bedrock through both mechanical and chemical processes.
The Kankakee Outwash Plain is a flat plain interspersed with sand dunes in the Kankakee River valley in northwestern Indiana and northeastern Illinois of the United States. It is just south of the Valparaiso Moraine and was formed during the Wisconsin Glaciation. As the glacier stopped at the Valparaiso Moraine, its meltwater was carried away to the outwash plain. On the south side of the moraine, where the elevation drops, the meltwaters eroded away valleys, carrying sand and mud with them. As the muddy meltwater reached the valley where the slope lessened, the water slowed, depositing the sand on the outwash plain. This created a smooth, flat, and sandy plain. Before its draining, the Kankakee Marsh, located on the outwash plain, was one of the largest freshwater marshes in the United States.
The Geology of Yorkshire in northern England shows a very close relationship between the major topographical areas and the geological period in which their rocks were formed. The rocks of the Pennine chain of hills in the west are of Carboniferous origin whilst those of the central vale are Permo-Triassic. The North York Moors in the north-east of the county are Jurassic in age while the Yorkshire Wolds to the south east are Cretaceous chalk uplands. The plain of Holderness and the Humberhead levels both owe their present form to the Quaternary ice ages. The strata become gradually younger from west to east.
The Kittatinny Valley is a section of the Great Appalachian Valley in Sussex and Warren counties in northwestern New Jersey that is bounded on the northwest by Kittatinny Mountain, and in the southeast by the New Jersey Highlands region. The valley is roughly 40 miles (64 km) long, with a breadth of 10 to 13 miles.
New England is a region in the North Eastern United States consisting of the states Rhode Island, Connecticut, Massachusetts, New Hampshire, Vermont, and Maine. Most of New England consists geologically of volcanic island arcs that accreted onto the eastern edge of the Laurentian Craton in prehistoric times. Much of the bedrock found in New England is heavily metamorphosed due to the numerous mountain building events that occurred in the region. These events culminated in the formation of Pangaea; the coastline as it exists today was created by rifting during the Jurassic and Cretaceous periods. The most recent rock layers are glacial conglomerates.
The geology of Massachusetts includes numerous units of volcanic, intrusive igneous, metamorphic and sedimentary rocks formed within the last 1.2 billion years. The oldest formations are gneiss rocks in the Berkshires, which were metamorphosed from older rocks during the Proterozoic Grenville orogeny as the proto-North American continent Laurentia collided against proto-South America. Throughout the Paleozoic, overlapping the rapid diversification of multi-cellular life, a series of six island arcs collided with the Laurentian continental margin. Also termed continental terranes, these sections of continental rock typically formed offshore or onshore of the proto-African continent Gondwana and in many cases had experienced volcanic events and faulting before joining the Laurentian continent. These sequential collisions metamorphosed new rocks from sediments, created uplands and faults and resulted in widespread volcanic activity. Simultaneously, the collisions raised the Appalachian Mountains to the height of the current day Himalayas.
The geology of North America is a subject of regional geology and covers the North American continent, the third-largest in the world. Geologic units and processes are investigated on a large scale to reach a synthesized picture of the geological development of the continent.
Lake Kankakee formed 14,000 years before present (YBP) in the valley of the Kankakee River. It developed from the outwash of the Michigan Lobe, Saginaw Lobe, and the Huron-Erie Lobe of the Wisconsin glaciation. These three ice sheets formed a basin across Northwestern Indiana. It was a time when the glaciers were receding, but had stopped for a thousand years in these locations. The lake drained about 13,000 YBP, until reaching the level of the Momence Ledge. The outcropping of limestone created an artificial base level, holding water throughout the upper basin, creating the Grand Kankakee Marsh.
The geology of Alaska includes Precambrian igneous and metamorphic rocks formed in offshore terranes and added to the western margin of North America from the Paleozoic through modern times. The region was submerged for much of the Paleozoic and Mesozoic and formed extensive oil and gas reserves due to tectonic activity in the Arctic Ocean. Alaska was largely ice free during the Pleistocene, allowing humans to migrate into the Americas.