New Haven, New Haven Co., Connecticut, USA
|Latitude & Longitude (WGS84):||41° 18' 27'' North , 72° 55' 34'' West|
|Latitude & Longitude (decimal):||41.30756,-72.92621|
|Köppen climate type:||Cfa : Humid subtropical climate|
A city first settled by Europeans in 1638 and incorporated as a city in 1784. It is the home of Yale University and the Yale-Peabody Museum, which houses a substantial world-wide mineral collection. Surrounding towns (such as East and West Haven and Hamden) were separated from New Haven over the centuries since its incorporation, leading to the inclusion of minerals in old or general references (like Robinson (1825), Schairer (1931), Sohon (1951), Januzzi (1976)), that are now attributable to these other towns or where just noted as "near" New Haven.
The bedrock geology of New Haven consists mostly of rocks within the Early Mesozoic Hartford Basin, part of the Newark Supergroup of rift basins. These rocks are mostly the Triassic New Haven Arkose with prominent ridges at West and East Rocks underlain by the Jurassic West Rock Diabase sill/dike complex. Other Jurassic dikes form smaller ridges along the east city border and cutting West Rock just north of the state Route 15 tunnel. Quarrying of diabase has produced prehnite, calcite, zeolites, and apophyllite attributed to New Haven, but these quarries (most notably Pine Rock Quarry in Hamden) are now mostly not in the city due to subdividing mentioned above. The extreme NW corner of New Haven, west of state Route 69 and Forest Road, is underlain by Ordovician to Silurian metamorphic rocks of the Orange-Milford Terrane, with the nonconformity between these and the overlying New Haven Arkose exposed at the foot of powerline pylons at the retail plaza on state Route 63 immediately north of state Route 15. The Milford-Orange Terrane includes serpentinite bodies, one of which, in the Malby Lakes area of West Haven, was quarried by Benjamin Silliman in the 1810s, but none of these is within New Haven's limits due to subdivision. In the extreme SE corner of the city, at Lighthouse Point, is an exposure of granite that is part of the Gander Terrane.
Coordinates are for the middle of the town green, which is the center of the original nine squares laid out for development by the first European settlers.
Mineral ListMineral list contains entries from the region specified including sub-localities
9 valid minerals.
Rock Types Recorded
Rock list contains entries from the region specified including sub-localities
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Entries shown in red are rocks recorded for this region.
This geological map and associated information on rock units at or nearby to the coordinates given for this locality is based on relatively small scale geological maps provided by various national Geological Surveys. This does not necessarily represent the complete geology at this locality but it gives a background for the region in which it is found.
Click on geological units on the map for more information. Click here to view full-screen map on Macrostrat.org
|Early Jurassic - Late Triassic|
174.1 - 237 Ma
|New Haven Arkose|
Age: Mesozoic (174.1 - 237 Ma)
Stratigraphic Name: New Haven Arkose
Description: Red, pink, and gray coarse-grained, locally conglomeratic, poorly sorted and indurated arkose, interbedded with brick-red micaceous, locally shaly siltstone and fine-grained feldspathic clayey sandstone.
Reference: Horton, J.D., C.A. San Juan, and D.B. Stoeser. The State Geologic Map Compilation (SGMC) geodatabase of the conterminous United States. doi: 10.3133/ds1052. U.S. Geological Survey Data Series 1052. 
Localities in this Region
Januzzi, Ronald E. and David Seaman (1976), Mineral Localities of Connecticut and Southeastern New York State and Pegmatite Minerals of the World. The Mineralogical Press, Danbury, Connecticut.