Eastend Formation
Encyclopedia
The Eastend Formation is a stratigraphical
unit of Maastrichtian
age
in the Western Canadian Sedimentary Basin
.
It takes the name from the town of Eastend
, and was first described in outcrop around the settlement by L.S. Russell in 1932. The type locality was later defined south-west of the town by W.O. Kupsch in 1956.
with volcanic grains, concretionary layers and green-grey shale
beds.
Coal
beds are found in southern Alberta
.
lies directly over the Bearpaw Formation
.
. In the Frenchman River
valley, the Eastend Formation is erosion
ally overlain by the Frenchman Formation
.
It is equivalent to St. Mary River Formation
and Horseshoe Canyon Formation
in southern Alberta
, as well as the Fox Hills Formation
in Montana
and North Dakota
.
Stratigraphy
Stratigraphy, a branch of geology, studies rock layers and layering . It is primarily used in the study of sedimentary and layered volcanic rocks....
unit of Maastrichtian
Maastrichtian
The Maastrichtian is, in the ICS' geologic timescale, the latest age or upper stage of the Late Cretaceous epoch or Upper Cretaceous series, the Cretaceous period or system, and of the Mesozoic era or erathem. It spanned from 70.6 ± 0.6 Ma to 65.5 ± 0.3 Ma...
age
Geochronology
Geochronology is the science of determining the age of rocks, fossils, and sediments, within a certain degree of uncertainty inherent to the method used. A variety of dating methods are used by geologists to achieve this, and schemes of classification and terminology have been proposed...
in the Western Canadian Sedimentary Basin
Western Canadian Sedimentary Basin
The Western Canadian Sedimentary Basin is a vast sedimentary basin underlying of Western Canada including southwestern Manitoba, southern Saskatchewan, Alberta, northeastern British Columbia and the southwest corner of the Northwest Territories. It consists of a massive wedge of sedimentary rock...
.
It takes the name from the town of Eastend
Eastend, Saskatchewan
-Infrastructure:The Saskatchewan Transportation Company provides intercity passenger and parcel express service to Eastend.-Attractions:Local Attractions:...
, and was first described in outcrop around the settlement by L.S. Russell in 1932. The type locality was later defined south-west of the town by W.O. Kupsch in 1956.
Lithology
The Eastend Formation is composed lithic sandstoneSandstone
Sandstone is a sedimentary rock composed mainly of sand-sized minerals or rock grains.Most sandstone is composed of quartz and/or feldspar because these are the most common minerals in the Earth's crust. Like sand, sandstone may be any colour, but the most common colours are tan, brown, yellow,...
with volcanic grains, concretionary layers and green-grey shale
Shale
Shale is a fine-grained, clastic sedimentary rock composed of mud that is a mix of flakes of clay minerals and tiny fragments of other minerals, especially quartz and calcite. The ratio of clay to other minerals is variable. Shale is characterized by breaks along thin laminae or parallel layering...
beds.
Coal
Coal
Coal is a combustible black or brownish-black sedimentary rock usually occurring in rock strata in layers or veins called coal beds or coal seams. The harder forms, such as anthracite coal, can be regarded as metamorphic rock because of later exposure to elevated temperature and pressure...
beds are found in southern Alberta
Southern Alberta
Southern Alberta is a region located in the Canadian province of Alberta. As of the year 2004, the region's population was approximately 272,017. The primary cities are Lethbridge and Medicine Hat...
.
Distribution
The Eastend Formation reaches a thickness of 30 metres (98.4 ft) near the town of Eastend. It is eroded to the north and east, where the Frenchman FormationFrenchman Formation
The Frenchman Formation is a division of Upper Cretaceous rocks found in Saskatchewan, Canada. More accurately described as Late Maastrichtian, these rocks contain the youngest of dinosaur genera, much like the Hell Creek Formation in the United States....
lies directly over the Bearpaw Formation
Bearpaw Formation
The Bearpaw Formation, also called the Bearpaw Shale, is a sedimentary rock formation found in northwestern North America. It is exposed in the U.S. state of Montana, as well as the Canadian provinces of Alberta and Saskatchewan, east of the Rocky Mountains...
.
Relationship to other units
The Eastend Formation is conformably overlain by the Whitemud Formation and gradually overlies the Bearpaw FormationBearpaw Formation
The Bearpaw Formation, also called the Bearpaw Shale, is a sedimentary rock formation found in northwestern North America. It is exposed in the U.S. state of Montana, as well as the Canadian provinces of Alberta and Saskatchewan, east of the Rocky Mountains...
. In the Frenchman River
Frenchman River
Frenchman River, or Frenchman Creek, is a river in Saskatchewan, Canada and Montana, United States. It is a tributary of the Milk River, itself a tributary of the Missouri.The river is approximately long....
valley, the Eastend Formation is erosion
Erosion
Erosion is when materials are removed from the surface and changed into something else. It only works by hydraulic actions and transport of solids in the natural environment, and leads to the deposition of these materials elsewhere...
ally overlain by the Frenchman Formation
Frenchman Formation
The Frenchman Formation is a division of Upper Cretaceous rocks found in Saskatchewan, Canada. More accurately described as Late Maastrichtian, these rocks contain the youngest of dinosaur genera, much like the Hell Creek Formation in the United States....
.
It is equivalent to St. Mary River Formation
St. Mary River Formation
The St. Mary River Formation is a geological formation in Alberta, Canada whose strata date back to the Late Cretaceous. Dinosaur remains are among the fossils that have been recovered from the formation. The St. Mary River Formation has produced only a few dinosaur fossils in its Albertan...
and Horseshoe Canyon Formation
Horseshoe Canyon Formation
The Horseshoe Canyon Formation is part of the Edmonton Group and is up to 230m in thickness. It is Late Campanian to Early Maastrichtian in age and is composed of mudstone, sandstone, and carbonaceous shales...
in southern Alberta
Southern Alberta
Southern Alberta is a region located in the Canadian province of Alberta. As of the year 2004, the region's population was approximately 272,017. The primary cities are Lethbridge and Medicine Hat...
, as well as the Fox Hills Formation
Fox Hills Formation
The Fox Hills Formation is a Cretaceous geologic formation in the northwestern Great Plains of North America. It is present from Alberta on the north to Colorado in the south....
in Montana
Montana
Montana is a state in the Western United States. The western third of Montana contains numerous mountain ranges. Smaller, "island ranges" are found in the central third of the state, for a total of 77 named ranges of the Rocky Mountains. This geographical fact is reflected in the state's name,...
and North Dakota
North Dakota
North Dakota is a state located in the Midwestern region of the United States of America, along the Canadian border. The state is bordered by Canada to the north, Minnesota to the east, South Dakota to the south and Montana to the west. North Dakota is the 19th-largest state by area in the U.S....
.