The Pakowki Formation is a stratigraphical

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 Campanian

Campanian

The Campanian is, in the ICS' geologic timescale, the fifth of six ages of the Late Cretaceous epoch . The Campanian spans the time from 83.5 ± 0.7 Ma to 70.6 ± 0.6 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 Pakowki Lake

Pakowki Lake

Pakowki Lake is an endorheic lake in Alberta, Canada located south of Etzikom, Alberta and not far north is the former town site of Pakowki which may have received it's name from the lake....

, and was first described in outcrop along the Pakowki Coulee by D.B. Dowling in 1916.

Lithology

The Formation is composed of grey mudstone

Mudstone

Mudstone is a fine grained sedimentary rock whose original constituents were clays or muds. Grain size is up to 0.0625 mm with individual grains too small to be distinguished without a microscope. With increased pressure over time the platey clay minerals may become aligned, with the...

.

Olive siltstone

Siltstone

Siltstone is a sedimentary rock which has a grain size in the silt range, finer than sandstone and coarser than claystones.- Description :As its name implies, it is primarily composed of silt sized particles, defined as grains 1/16 - 1/256 mm or 4 to 8 on the Krumbein phi scale...

 and very fine grained sandstone

Sandstone

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,...

 can occur locally. A thin pebble conglomerate

Conglomerate (geology)

A conglomerate is a rock consisting of individual clasts within a finer-grained matrix that have become cemented together. Conglomerates are sedimentary rocks consisting of rounded fragments and are thus differentiated from breccias, which consist of angular clasts...

 marks the base.

Distribution

The Pakowki Formation reaches a maximum thickness of 200 metres (656.2 ft) in central Saskatchewan

Saskatchewan

Saskatchewan is a prairie province in Canada, which has an area of . Saskatchewan is bordered on the west by Alberta, on the north by the Northwest Territories, on the east by Manitoba, and on the south by the U.S. states of Montana and North Dakota....

. It reaches into 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...

, thinning out as it progresses westwards towards the Canadian Rockies

Canadian Rockies

The Canadian Rockies comprise the Canadian segment of the North American Rocky Mountains range. They are the eastern part of the Canadian Cordillera, extending from the Interior Plains of Alberta to the Rocky Mountain Trench of British Columbia. The southern end borders Idaho and Montana of the USA...

 foothills.

Relationship to other units

The Pakowki Formation is abruptly overlain by the Milk River Formation

Milk River Formation

The Milk River Formation is a near- shore to terrestrial sedimentary unit deposited during the Late Cretaceous in southern Alberta...

 and gradationally overlays the Judith River Formation

Judith River Formation

The Judith River Formation is a fossil-bearing geologic formation in Montana, and is part of the Judith River Group. It dates to the upper Cretaceous, between 80 and 75 million years ago, corresponding to the "Judithian" land vertebrate age...

 or Foremost Formation

Foremost Formation

The Foremost 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.-Dinosaurs:...

.

It is equivalent to the upper part of the Lea Park Formation

Lea Park Formation

The Lea Park Formation is a stratigraphical unit of Late Cretaceous age in the Western Canadian Sedimentary Basin, Canada.It takes the name from the settlement of Lea Park, Alberta, located north-west of Lloydminster on the banks of the North Saskatchewan River. It was first defined in an outcrop...

 in central Alberta

Central Alberta

Central Alberta is a region located in the Canadian province of Alberta.Central Alberta is the most densely populated rural area in the province...

. It is not differentiated from the Riding Mountain Formation to the east into eastern Saskatchewan

Saskatchewan

Saskatchewan is a prairie province in Canada, which has an area of . Saskatchewan is bordered on the west by Alberta, on the north by the Northwest Territories, on the east by Manitoba, and on the south by the U.S. states of Montana and North Dakota....

 and Manitoba

Manitoba

Manitoba is a Canadian prairie province with an area of . The province has over 110,000 lakes and has a largely continental climate because of its flat topography. Agriculture, mostly concentrated in the fertile southern and western parts of the province, is vital to the province's economy; other...

.