Stevns Klint, known as the Cliffs of Stevns in English, is a white chalk cliff located some southeast of Store Heddinge on the Danish island of

Zealand Zealand ( ) is the largest and most populous islands of Denmark, island in Denmark proper (thus excluding Greenland and Disko Island, which are larger in size) at 7,031 km2 (2715 sq. mi.). Zealand had a population of 2,319,705 on 1 Januar ...

. Stretching along the coast, it is of geological importance as one of the best exposed Cretaceous-Tertiary (K/T) boundaries in the world. Subject to frequent erosion, the cliff rises to a height of up to . Because of its exceptional fossil record, Stevns Klint was inscribed on the

UNESCO The United Nations Educational, Scientific and Cultural Organization (UNESCO ) is a List of specialized agencies of the United Nations, specialized agency of the United Nations (UN) with the aim of promoting world peace and International secur ...

World Heritage List World Heritage Sites are landmarks and areas with legal protection under an international treaty administered by UNESCO for having cultural, historical, or scientific significance. The sites are judged to contain "cultural and natural heritag ...

in 2014.

Geology

The cliff reveals sections from the uppermost part of the

Maastrichtian The Maastrichtian ( ) is, in the International Commission on Stratigraphy (ICS) geologic timescale, the latest age (geology), age (uppermost stage (stratigraphy), stage) of the Late Cretaceous epoch (geology), Epoch or Upper Cretaceous series (s ...

stage (72 to 66 million years ago), known as the Tor Formation and from the lowermost part of the

Danian The Danian is the oldest age or lowest stage of the Paleocene Epoch or Series, of the Paleogene Period or System, and of the Cenozoic Era or Erathem. The beginning of the Danian (and the end of the preceding Maastrichtian) is at the Cretac ...

stage (66 to 62 million years ago); the Danian-aged rocks are known as the Rødvig Formation and the Stevns Klint Formation. The lower strata from the cliff are from the Cretaceous and are composed of soft

chalk Chalk is a soft, white, porous, sedimentary carbonate rock. It is a form of limestone composed of the mineral calcite and originally formed deep under the sea by the compression of microscopic plankton that had settled to the sea floor. Ch ...

, indicating a relatively deep marine depositional environment. The dark layer of , mainly five to ten centimeters thick, clearly marks the

Cretaceous–Paleogene boundary The Cretaceous–Paleogene (K–Pg) boundary, formerly known as the Cretaceous–Tertiary (K–T) boundary, is a geological signature, usually a thin band of rock containing much more iridium than other bands. The K–Pg boundary marks the end o ...

. The is enriched in

iridium Iridium is a chemical element; it has the symbol Ir and atomic number 77. This very hard, brittle, silvery-white transition metal of the platinum group, is considered the second-densest naturally occurring metal (after osmium) with a density ...

, a fact used as an argument for the

Alvarez hypothesis The Alvarez hypothesis posits that the Extinction event, mass extinction of the non-avian dinosaurs and many other living things during the Cretaceous–Paleogene extinction event was caused by the Impact event, impact of a large asteroid on the Ea ...

that the worldwide Cretaceous–Paleogene mass extinction was caused by the impact of an asteroid. Following the boundary is a layer of darker clay and chalk between 10 and 30 cm thick, corresponding to a period of low biological diversity on the sea floor immediately after the K-Pg Boundary. The layers can also be seen deep in the tunnels of Stevnsfortet, a cold-war fortress constructed in 1953. The upper layers of the cliff consist of

bryozoa Bryozoa (also known as the Polyzoa, Ectoprocta or commonly as moss animals) are a phylum of simple, aquatic animal, aquatic invertebrate animals, nearly all living in sedentary Colony (biology), colonies. Typically about long, they have a spe ...

and were deposited during the early Paleogene. The

in the cliff is highly shock resistant to both conventional and nuclear weapons.

Paleontology

Stevns Klint contains a remarkably detailed and complete fossil record of the biota in Northern Europe during the late Cretaceous and early Paleogene. The Cretaceous chalk at Stevns Klint contains more than 450 species of macrofossils and hundreds more species of microfossils. The lower Paleogene layers are similarly rich in microfossils, containing many species of millimeter-long suspension feeders. A wide variety of

benthic The benthic zone is the ecological region at the lowest level of a body of water such as an ocean, lake, or stream, including the sediment surface and some sub-surface layers. The name comes from the Ancient Greek word (), meaning "the depths". ...

foraminifera Foraminifera ( ; Latin for "hole bearers"; informally called "forams") are unicellular organism, single-celled organisms, members of a phylum or class (biology), class of Rhizarian protists characterized by streaming granular Ectoplasm (cell bio ...

species have been identified from the Cretaceous and Paleogene, with significant differences in abundance across the K–Pg boundary demonstrating the biotic turnover that occurred during the mass extinction event. '' Corbulamella'', a bivalve known as a

pioneer species Pioneer species are resilient species that are the first to colonize barren environments, or to repopulate disrupted biodiverse steady-state ecosystems as part of ecological succession. Various kinds of events can create good conditions for pi ...

, dominate the strata immediately after the boundary layer. In total, over 830 species of macrofauna have been identified from Stevns Klint. These include

bryozoans Bryozoa (also known as the Polyzoa, Ectoprocta or commonly as moss animals) are a phylum of simple, aquatic animal, aquatic invertebrate animals, nearly all living in sedentary Colony (biology), colonies. Typically about long, they have a spe ...

brachiopods Brachiopods (), phylum Brachiopoda, are a phylum of animals that have hard "valves" (shells) on the upper and lower surfaces, unlike the left and right arrangement in bivalve molluscs. Brachiopod valves are hinged at the rear end, while the fron ...

ammonites Ammonoids are extinct, (typically) coiled-shelled cephalopods comprising the subclass Ammonoidea. They are more closely related to living octopuses, squid, and cuttlefish (which comprise the clade Coleoidea) than they are to nautiluses (family N ...

corals Corals are colonial marine invertebrates within the subphylum Anthozoa of the phylum Cnidaria. They typically form compact Colony (biology), colonies of many identical individual polyp (zoology), polyps. Coral species include the important Coral ...

crustaceans Crustaceans (from Latin meaning: "those with shells" or "crusted ones") are invertebrate animals that constitute one group of Arthropod, arthropods that are traditionally a part of the subphylum Crustacea (), a large, diverse group of mainly aquat ...

, and the remains of some larger animals like

sharks Sharks are a group of elasmobranch cartilaginous fish characterized by a ribless endoskeleton, dermal denticles, five to seven gill slits on each side, and pectoral fins that are not fused to the head. Modern sharks are classified within the ...

. Stevns Klint was the first known site to document the short-term survival of ammonites into the

Paleogene The Paleogene Period ( ; also spelled Palaeogene or Palæogene) is a geologic period and system that spans 43 million years from the end of the Cretaceous Period Ma (million years ago) to the beginning of the Neogene Period Ma. It is the fir ...

, when they were originally thought to have gone extinct at the K-pg boundary.

Cold War museum

In 2008 Cold War Museum Stevns Fortress opened to the public. It features a large exhibition of military equipment and a 1.5-hour guided tour in the large underground system of the fortress. The underground system of the fortress features of tunnels, living quarters and command centers, including a hospital and a chapel. There are also two ammunition depots for its two cannons. The tunnels are below the surface, dug deep into the chalk of Stevns. The top-secret fortress was built in 1953 and remained operational until 2000.

Højerup Church

The old Højerup Church (''Højerup Gamle Kirke'') which stands at the top of the cliff dates from the year 1200. As a result of erosion, a landslide in 1928 caused the

chancel In church architecture, the chancel is the space around the altar, including the Choir (architecture), choir and the sanctuary (sometimes called the presbytery), at the liturgical east end of a traditional Christian church building. It may termi ...

to collapse and fall to the shore below. The cliff can be accessed via steps from the church. A new church completed in 1913 is located back from the cliff.

UNESCO listing

On 23 June 2014 it was announced that Stevns Klint and the

Wadden Sea The Wadden Sea ( ; ; or ; ; ; ) is an intertidal zone in the southeastern part of the North Sea. It lies between the coast of northwestern continental Europe and the range of low-lying Frisian Islands, forming a shallow body of water with tida ...

had been added to the UNESCO list of

World Heritage Site World Heritage Sites are landmarks and areas with legal protection under an treaty, international treaty administered by UNESCO for having cultural, historical, or scientific significance. The sites are judged to contain "cultural and natural ...

s in Denmark.

Explanatory notes

References

External links

*
Official website
{{Authority control Cliffs of Denmark Coastline of Zealand Geology of Denmark Museums in Region Zealand Stevns Municipality Tourist attractions in Stevns Municipality World Heritage Sites in Denmark