New maps highlight geologic characteristics of U.S. tight oil, shale plays

Energy Information Administration ^ | APRIL 17, 2015 | Energy Information Administration

[thackney]

EIA is currently in the process of updating maps of major tight oil and shale gas plays, including the Eagle Ford and Marcellus plays, which will help to better characterize the geology of key areas of production in the United States. EIA's most recent maps focus on shale and tight oil plays, and characterize plays based on geologic characteristics, including rock type and age. Understanding geologic history and processes helps exploration and production companies reduce the risk of drilling dry, nonproducing wells and better understand hydrocarbon resource potentials.

Production of crude oil and natural gas occurs in two classes of rock: source rocks and reservoir rocks. Source rocks are sedimentary rocks in which hydrocarbons (organic chemical compounds of hydrogen and carbon) form. Reservoir rocks are both porous, meaning that there are open spaces, or voids, within the rock, and permeable, meaning fluids are able to flow within them. After forming in the source rock, hydrocarbons, which can vary from simple structures, like methane (a constituent of natural gas), to very complex structures, like bitumen (contained in tar sands), can migrate to the reservoir rock.

Historically, nearly all hydrocarbons produced domestically were withdrawn from carbonate and sandstone reservoirs. However, over the past decade, production from shale and other tight rock formations, spurred by advances in exploration and production technology, has grown dramatically.

Geologic formations that contain oil and gas include clastic or detrital rocks (formed from pieces of pre-existing rocks or minerals), chemical rocks (formed by chemical precipitation of minerals), and organic rocks (formed by biological debris from shells, plant material, and skeletons). The three most common sedimentary rock types encountered in oil and gas fields are shales, sandstones, and carbonates.

Classifying these rock types primarily depends on characteristics such as grain size and composition, porosity (pore space within and between grains), and cement (a chemically formed material that holds the grains together), each of which can influence oil and gas production.

Shale is formed by the accumulation of very small sediments deposited in deep water, at the bottoms of rivers, lakes, and oceans. Shales are the most abundant clastic sedimentary rock, and because of their potential for a high organic content, shales are considered to be the primary source rocks for hydrocarbons.

Sandstone is created by larger sediment, deposited in deserts, river channels, deltas, and shallow sea environments. These rocks tend to be more porous than shales, and consequently make excellent reservoir rocks. Sandstone is the second most abundant clastic sedimentary rock and is the most commonly encountered reservoir rock in hydrocarbon production. Carbonate is created by the accumulation of shells and skeletal remains of water-dwelling organisms in marine environments. The third most abundant sedimentary rock, carbonate (e.g., limestone) rocks are also very good reservoirs and are commonly encountered during hydrocarbon production.

Geologic age is an important determinant of hydrocarbon potential, beyond the characteristics of source and reservoir rocks. Identifying fossils, other chemical markers, and correlating rocks across different formations allows earth scientists to determine the age of the rock and to understand the processes that influenced the sediments and organic material over time.

While many rocks of different ages produce oil and natural gas, domestic areas of prolific production include formations from several different geologic periods: the Devonian (416 to 359 million years ago (mya), the Carboniferous (359 to 299 mya), the Permian (299 to 251 mya), and the Cretaceous (145 to 65 mya). During these periods, organic-rich materials accumulated and, over time, heat and pressure chemically altered originally organic chemicals into natural gas and oil.

[thackney]

[thackney]

I was going to post the rest of the updated maps.

It appears so far, that is the only update.

Maps: Exploration, Resources, Reserves, and Production
http://www.eia.gov/pub/oil_gas/natural_gas/analysis_publications/maps/maps.htm

[Mouton]

From what I gather elsewhere, the drill/development costs vary wildly between these areas also. Eagle/Ford I believe is one of the lower cost ($60 per barrel) while some areas make the breakeven point over $100 per barrel. Accordingly the rig counts in the higher cost areas have been dropping like a prom queen’s dress in those highest cost areas. Even so, some companies which are only developing in the lower cost areas are strangled by huge debt loads and the service cost to those loans has caused them to reduce exploration markedly this year as hedges have almost all expired by June. I have bet on some of these companies but the jury is out whether they will survive.

[thackney]

From what I gather elsewhere, the drill/development costs vary wildly between these areas also. Eagle/Ford I believe is one of the lower cost ($60 per barrel) while some areas make the breakeven point over $100 per barrel.

They vary widely within the same play as well. Several counties in the Bakken is under $35 while the drilling peak the average was likely more than double.

This year the average breakeven cost in each play is going to be far lower, if only because the more expensive areas won't be drilled this year and will lower the average cost.

[struggle]

The small play south of Charlotte, NC isn’t on there...must be too small.

[thackney]

They are small, the deep river basin and the dan river basin. I don't think their is any significant production from them.

Hydrocarbon Source Rocks in the Deep River and Dan River Triassic Basins, North Carolina
http://pubs.usgs.gov/of/2008/1108/ofr2008-1108.pdf

[thackney]

There is currently no drilling in North Carolina.

INVESTOR RELATIONS >RIG COUNTS >INTERACTIVE RIG COUNTS
zoom-able, search-able map
http://gis.bakerhughesdirect.com/RigCounts/default2.aspx

[thackney]

My number by memory was off by a couple bucks.

In January, the North Dakota Department of Mineral Resources produced the following list of break even costs per county:

https://www.dmr.nd.gov/oilgas/presentations/FullHouseAppropriations010815.pdf
Page 7

Billings $44
BOT-REN $52
BOW-SLP $75
Burke $62
Divide $73
Dunn $29
Golden Valley $52
McKenzie $30
McLean $77
Mountrail $41
Stark $37
Williams $36

[Red Badger]

I see they are considering drills in SW Mississippi.

I guess the oil is loosa there...............(Groucho Marx reference......)

[Red Badger]

Question:

There are oil wells in NW Florida near Jay, Fl. I don’t see anything on the map for there, except ‘Basin’. What is that? A place where oil ‘could’ be?..............

[thackney]

This is not traditional fields.

It is only tight formations like shale plays.

Sedimentary basins are regions where considerable thicknesses of sediments have accumulated (in places up to 20 km). Sedimentary basins are widespread both onshore and offshore. It may or may not contain commercial quantities of oil/gas.

http://www.tcd.ie/Geology/assets/pdf/geology-for-engineers/L09_basins.pdf

[Red Badger]

Thanks!...............Maybe I should drill in my backyard................

[thackney]

Do you have at least 40 acres?

[Red Badger]

No and I don’t have a mule, either.

Do two dogs and a ferret count?...............

[thackney]

Animals are probably not going to give you enough help in having sufficient mineral rights.

You are going to need to form a co-op with your neighbors.

;-)

[Red Badger]

My neighbor has some chickens..............That’ll help...........