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Site content related to keyword: "fossils"

Finding faults - Delaware Geological Survey discovers evidence of past earthquakes

Delaware Geological Survey scientists found slickensides in core samples indicating faults in northern Delaware.

Delaware Geological Survey (DGS) scientists have uncovered hard proof of faults in northern Delaware, indicating the occurrence of earthquakes millions of years ago.

Monitoring our water - Delaware Geological Survey improving groundwater monitoring efforts with new wells, sampling

Scott Andres examines sediment samples extracted from more than 500 feet underground for clues about the amount and quality of water available in central Delaware.

Delaware Geological Survey improving groundwater monitoring efforts with new wells, sampling. Scientists are digging for answers about the amount and quality of water available underground in central Delaware, where ongoing development will put increasing demands on water supplies in the coming decade.

The Delaware Geological Survey (DGS) is installing 7,700 feet of wells at eight sites in southern New Castle and northern Kent counties to improve groundwater-monitoring efforts, supported by a $600,000 grant from the Delaware Department of Natural Resources and Environmental Control (DNREC). Groundwater is the primary source of drinking water south of the Chesapeake and Delaware Canal, and populations there are projected to continue expanding.

DGS Geologic Map No. 16 (Fairmont Rehoboth Beach Quadrangles) Dataset

DGS Geologic Map No. 16 (Fairmont Rehoboth Beach Quadrangles) Dataset

This vector data set contains the rock unit polygons for the surficial geology in the Delaware Coastal Plain covered by DGS Geologic Map No. 16 (Fairmount and Rehoboth Beach quadrangles). The geologic history of the surficial units of the Fairmount and Rehoboth Beach quadrangles is that of deposition of the Beaverdam Formation and its subsequent modification by erosion and deposition related to sea-level fluctuations during the Pleistocene. The geology reflects this complex history both onshore, in Rehoboth Bay, and offshore. Erosion during the late Pleistocene sea-level low stand and ongoing deposition offshore and in Rehoboth Bay during the Holocene rise in sea level represent the last of several cycles of erosion and deposition.

To facilitate the GIS community of Delaware and to release the geologic map of the Fairmount and Rehoboth Beach quadrangles with all cartographic elements (including geologic symbology, text, etc.) in a form usable in a GIS, we have released this digital coverage of DGS Geological Map 16. The update of earlier work and mapping of new units is important not only to geologists, but also to hydrologists who wish to understand the distribution of water resources, to engineers who need bedrock information during construction of roads and buildings, to government officials and agencies who are planning for residential and commercial growth, and to citizens who are curious about the bedrock under their homes. Formal names are assigned to all rock units according to the guidelines of the 1983 North American Stratigraphic Code (NACSN, 1983).

GM16 Geologic Map of the Fairmount and Rehoboth Beach Quadrangles, Delaware

GM16 Geologic Map of the Fairmount and Rehoboth Beach Quadrangles, Delaware

The geologic history of the surficial units of the Fairmount and Rehoboth Beach quadrangles is that of deposition of the Beaverdam Formation and its subsequent modification by erosion and deposition related to sea-level fluctuations during the Pleistocene. The geology reflects this complex history both onshore, in Rehoboth Bay, and offshore. Erosion during the late Pleistocene sea-level low stand and ongoing deposition offshore and in Rehoboth Bay during the Holocene rise in sea level represent the last of several cycles of erosion and deposition.

Fossil Identification Sheet

Pictures and brief descriptions of commonly found fossils in Delaware.

Dinosaurs in Delaware?

Only fragmentary remains of dinosaurs have been found in Delaware. All of these have come from the Chesapeake and Delaware Canal, mainly from the spoil piles created by the dredging of the Canal. Various nature groups in Delaware lead trips to the Canal for collecting. Most of the fossils found are those of marine invertebrates (primarily bivalves and gastropods with some remains of sponges, ammonites, and belemnites).

Thousands come out to celebrate the sea at Coast Day 2009

Coast Day visitor Brandon Herbert Mears at the ever popular critter touch tanks. Photo by Lisa Tossey

A 33-year tradition, Coast Day lets visitors learn more about the state's ocean and coastal resources as well as the work of CEOE researchers, Delaware Sea Grant, and their many partners.

DGS Digital Datasets

In the same ways as our printed publications, digital data released by the DGS represent the results of original professional research and as such are used by professionals and the public.

Marine Mammals: Phylum Chordata

Marine Mammals:  Phylum Chordata<br>Source:  seasky.org

The Pollack Farm Site, in the Cheswold sands of the lower Miocene Calvert Formation, produced a fragmentary marine mammal fauna. The Pollack location yielded at least six cetaceans (whales, porpoises), a sirenian(manatee), along with one of the earliest records of a true seal (Listed below).

Land Mammals: Phylum Chordata

Land Mammals:  Phylum Chordata<br>Source:  hedweb.com

Land mammal fossils were discovered in 1992 in the lower part of the Calvert formation at the Pollack Farm site. During the short time the pit was open, the collection grew to become the most diverse tertiary land mammal fauna known north of Florida on the eastern half of North America.

Birds: Phylum Chordata

Birds - Miocene Fossils <br>Source:  Wikimedia Commons

The lower Miocene Pollack Farm Fossil Site has yielded few avian fossils in comparison to the other classes of vertebrates and invertebrates. Only eleven fossil fragments, assignable to six taxa, were collected at the Pollack site. Of the eleven avian fossils collected, representations from three distinctive orders were recovered: Gaviiformes (divers and loons, seen below), Charadriiformes (gulls and shore birds), Pelecaniformes (cormorants and pelicans).

Reptiles: Phlyum Chordata

Reptiles: Phlyum Chordata<br>Source:  resalliance.org

The Pollack Farm Site has provided the first legitimate window of Miocene reptilian life in North America east of the great plains and north of Florida. In years prior to the excavation of the Pollack site, records of particular small lizards and snakes were non-existent in locations of the mid-Atlantic and northeast, thus providing a significant value to the Miocene fossils recovered.

Vertebrates: Phylum Chordata

Phylum Chordata includes the vertebrates. Although not as common as the invertebrates, teeth and bones from different classes of vertebrate animals can be found at Canal sites.

Starfish and Urchins: Phylum Echinodermata

Echinoderms are "spiny-skinned" invertebrate animals that live only in marine environments. Two major divisions are recognized by biologists: principally attached, usually stalked forms of the Pelmatozoa; and unattached free-moving forms of the Eleutherozoa.

Insects and Crustaceans: Phylum Arthropoda

Arthropods are animals with a segmented body, external skeleton, and jointed appendages. The Arthropoda includes insects and crustaceans. Only two groups of arthropods are common as fossils in the Cretaceous of the C&D Canal area, and both are types of crustaceans: the Malacostraca (crabs, lobsters, and shrimp) and the microscopic Ostracoda.

Segmented Worms: Phylum Annelida

Annelids are segmented worms. The remains of the soft-bodied segmented worms are not usually preserved as fossils. Some marine (salt-water) types, however, secrete tubes of calcium carbonate to use both as a home and to provide protection from their enemies. These tubes can be found as isolated specimens or attached to larger shells. Two genera, Serpula and Hamulus, are fairly common in formations near the C&D canal.

Clams, Snails, and Squid: Phylum Mollusca, Class Cephalopoda

Cephalopoda is the scientific name for the mollusc group that includes the chambered Nautilus, squid, and octopus. Two extinct types are found at the C & D canal: the Nautilus-like ammonites and the superficially squid-like belemnites. Ammonites are uncommon, especially complete specimens, but can be very useful for age determination. The belemnite species Belemnitella americana has been so abundant at some canal localities that it was named the state fossil of Delaware.

Clams, Snails, and Squid: Phylum Mollusca, Class Pelecypoda

Pelecypoda is the group of molluscs referred to as the bivalves. Most pelecypods have a pair of hinged shells of generally equal size. Clams, oysters, and scallops are well-known types. Pelecypods can be abundant in the sediments of the C & D canal area.

Clams, Snails, and Squid: Phylum Mollusca, Class Gastropoda

Gastropoda is the scientific name for the group of animals more commonly called snails. Gastropods have a single coiled or uncoiled shell and are common fossil types in the Cretaceous sediments of the C & D canal area.

RI50 Plant Microfossils of the Calvert Formation of Delaware

RI50 Plant Microfossils of the Calvert Formation of Delaware

The Calvert Formation, deposited in a shallow sea during the late Oligocene and early to middle Miocene (15-27 million years ago), contains a very rich fossil microflora, both in terms of number of specimens and number of species. Most abundant are pollen of oak, pine, and hickory, but exotic taxa (those that no longer occur in Delaware) are present in all samples of this formation. They include pollen of Engelhardia type, Manilkara, Planera (water elm), Alangium(?), and palms. All of these exotics are genera of subtropical or tropical regions, some occurring now in Central America, Florida, and east Asia. The climate during the deposition of the Calvert Formation was probably subtropical and moist.