What are 3 types of unconformities?

Commonly three types of unconformities are distinguished by geologists:


How do you identify an unconformity?

Unconformities are ancient surfaces of erosion and/or non-deposition that indicate a gap or hiatus in the stratigraphic record. An unconformity may be represented on a map by different type of line than that used for other contacts, and in cross-section is shown by a wavy or crenulated line.

What are the 4 types of unconformities?


  • Disconformity.
  • Nonconformity.
  • Angular unconformity.
  • Paraconformity.

What are the types of unconformity?

There are three kinds of unconformities: disconformities, nonconformities, and angular unconformities. Disconformities. Disconformities (Figure 1 ) are usually erosional contacts that are parallel to the bedding planes of the upper and lower rock units.

What causes an unconformity?

Unconformities are a type of geologic contact—a boundary between rocks—caused by a period of erosion or a pause in sediment accumulation, followed by the deposition of sediments anew.

What is another word for unconformity?

What is another word for unconformity?

nonconformity nonconformance
violation denial
disaffection discordance
lawlessness mutinousness
nonconsent recusance

What causes unconformity?

Why is it important to recognize an unconformity?

Recognition of unconformities is useful for subdividing stratigraphic units, determining the timing of tectonic activity, interpreting lateral facies relationships, constructing burial and uplift curves, correlating certain stratigraphic boundaries, interpreting sea-level changes, and for reconstructing paleogeography.

What is the principle of unconformity?

An unconformity represents a period during which deposition did not occur or erosion removed rock that had been deposited, so there are no rocks that represent events of Earth history during that span of time at that place.

What is meant by unconformity?

Put simply, an unconformity is a break in time in an otherwise continuous rock record. Unconformities are a type of geologic contact—a boundary between rocks—caused by a period of erosion or a pause in sediment accumulation, followed by the deposition of sediments anew.

What does nonconformity mean in English?

failure or refusal to
English Language Learners Definition of nonconformity : failure or refusal to behave the way most people behave : failure or refusal to conform. See the full definition for nonconformity in the English Language Learners Dictionary. nonconformity. noun.

What is the best example of an unconformity?

A good example is the North Sea Unconformity Complex, often called the ‘base-Cretaceous unconformity’ or the ‘Late-Cimmerian unconformity’. This is perhaps the most easily identifiable surface of the Phanerozoic succession of the Norwegian continental shelf.

What is the significance of an unconformity?

An unconformity represents time during which no sediments were preserved in a region. The local record for that time interval is missing and geologists must use other clues to discover that part of the geologic history of that area.

How does an unconformity formed?

Unconformities can form when sediment is not deposited in an area for a long time. If sediment is not deposited, no new layer of rock can form. Unconformities can also form when erosion removes a layer of rock after it formed. This is like someone taking a paper out of the stack.

What is an unconformity geology?

An unconformity is a gap in the sequence of rocks in a geologic column. It is a buried erosion surface separating two rock strata of different ages.

What is unconformity in geology?

An unconformity is a contact between two rock units in which the upper unit is usually much younger than the lower unit. Unconformities are typically buried erosional surfaces that can represent a break in the geologic record of hundreds of millions of years or more.