Search results
Results From The WOW.Com Content Network
Disconformity. A disconformity is an unconformity between parallel layers of sedimentary rocks which represents a period of erosion or non-deposition. [3] Disconformities are marked by features of subaerial erosion. This type of erosion can leave channels and paleosols in the rock record. [4]
Disconformity: the contact between younger and older beds is marked by visible, irregular erosional surfaces. Paleosol might develop right above the disconformity surface because of the non-deposition setting. Paraconformity: the bedding planes below and above the unconformity are parallel. A time gap is present, as shown by a faunal break, but ...
Angular unconformity when the earlier layers are tilted and eroded while the later layers are horizontally laid. Nonconformity if the early layers have no bedding in contrast to the later layers, ie. they are igneous or metamorphic rocks. Disconformity if both the early beds and the later beds are parallel to each other.
It also contains thin beds of shale and siltstone, and conglomerate. The Muav Limestone weathers to a dark gray or rusty-orange color and forms cliffs or small ledges. This formation varies between 45 and 254 m (148 and 833 ft) in thickness. Its upper contact is a disconformity with the overlying Frenchman Mountain Dolostone.
Within the Unkar Group, the contact between the Hakatai Shale and overlying Shinumo Sandstone is a distinct disconformity. This contact is the only significant unconformity that occurs within the Unkar Group. This disconformity is sharp and locally truncates cross-bedding and channels exhibited by sandstones in the underlying Hakatai Shale.
Sequence stratigraphy is a branch of geology, specifically a branch of stratigraphy, that attempts to discern and understand historic geology through time by subdividing and linking sedimentary deposits into unconformity bounded units on a variety of scales.
Hutton's Unconformity is a name given to various notable geological sites in Scotland identified by the 18th-century Scottish geologist James Hutton as places where the junction between two types of rock formations can be seen. This geological phenomenon marks the location where rock formations created at different times and by different ...
In the case of the unconformity between the Vishnu Basement Rocks and the Unkar Group, studies of the underlying Vishnu Basement Rocks indicate they were uplifted from a depth of about 25 km (16 mi) to a depth of about 10 km (6.2 mi), between 1.75 and 1.66 billion years ago, and from a depth of about 10 km (6.2 mi) to the weathered surface on ...