**Undiscovered Oil and Gas Resources Underlying the U.S. Portions of the
Great Lakes, 2005**

*The U.S. Geological Survey recently completed allocations of oil and
gas resources underlying the U.S. por­tions of the Great Lakes. These
allocations were developed from the oil and gas assessments of the U.S.
portions of the Appalachian Basin and the Michigan Basin. With the
completion of the assessments of these two basins, the fol­lowing
quantities of undiscovered, technically recoverable oil and gas
resources were allocated to the U.S. portions of the Great Lakes: (1) a
mean value of 312 million barrels of oil, (2) a mean value of 5.2
trillion cubic feet of natural gas, and (3) a mean value of 122 million
barrels of natural gas liquids.*

**Introduction**

The U.S. Geological Survey (USGS) completed an assessment of the
undiscovered oil and gas potential of the U.S. portions of the
Appa­lachian Basin and the Michigan Basin in 2002 and 2004, respectively.
Following the assessments of these two basins, oil and gas allocations
were assigned to the U.S. portions of the Great Lakes (fig. 1) --- Lake
Superior (Michigan, Minnesota, and Wisconsin), Lake Michigan (Illinois,
Indiana, Michigan, and Wisconsin), Lake Huron (Michigan), Lake Erie
(Michigan, New York, Ohio, and Pennsylvania), and Lake Ontario (New
York). Allocations for Lake St. Clair (Michigan) were included with
those of Lake Erie.

The allocations are based on the geologic elements of each total
petroleum system (TPS) defined in the region and the projected extent of
those elements from onshore beneath each of the lakes. These geo­logic
elements include the hydrocarbon source rocks, reservoir rocks, and
traps. By using this geologic framework, the USGS defined 8 total
petroleum systems and 21 assessment units (AUs) within the Great Lakes
and estimated the quantity of undiscovered technically recover­able oil
and gas resources within 16 of the 21 AUs in the Great Lakes (table 1).

**Total Petroleum Systems**

The eight total petroleum systems identified in the U.S. portions of the
Great Lakes are the (1) Precambrian Nonesuch TPS, (2) Ordovi­cian Foster
TPS, (3) \[Ordovician\] Utica-Lower Paleozoic TPS, (4) Ordovician to
Devonian Composite TPS, (5) Silurian Niagara/Salina TPS, (6) Devonian
Antrim TPS, (7) Devonian Shale-Middle and Upper Paleozoic TPS, and (8)
Pennsylvanian Saginaw TPS. Each TPS is named according to the petroleum
source rock(s) of that system. For most of the systems, each TPS is
associated with only one source rock. The Ordovician to Devonian
Composite TPS, however, is a composite petroleum system having
contributions from one or more of the follow­ing different source rocks:
Ordovician Collingwood Shale, Devonian Detroit River Group, and Devonian
Antrim Shale.

**Assessment Units**

Of the AUs, 13 are characterized as conventional oil and gas
accumu­lations, and 8 are characterized as continuous (unconventional)
accumula­tions. The 13 conventional AUs (and associated basins) are as
follows:

> Devonian to Mississippian Berea/Michigan Sandstones AU (Michigan
> Basin);
>
> Middle Devonian Carbonates AU, which includes the Detroit River Group,
> Dundee Limestone, and Traverse Group (Michigan Basin);
>
> \[Devonian\] Oriskany Sandstone-Stratigraphic AU (Appalachian Basin);
>
> Devonian Sylvania Sandstone AU (Michigan Basin);
>
> \[Silurian\] Lockport Dolomite AU (Appalachian Basin);
>
> Silurian A--1 Carbonate AU (Michigan Basin);
>
> Silurian Niagara AU (Michigan Basin);
>
> Silurian Burnt Bluff AU (Michigan Basin);
>
> \[Ordovician\] Black River-Trenton Hydrothermal Dolomite AU
> (Appalachian Basin);
>
> Ordovician Trenton/Black River AU (Michigan Basin);
>
> \[Ordovician\] Knox Unconformity AU (Appalachian Basin);
>
> Ordovician Sandstones and Carbonates AU, which includes the Prairie du
> Chien Group, St. Peter Sandstone, Glenwood Formation, and equivalent
> stratigraphic units (Michigan Basin); and
>
> Precambrian Nonesuch AU (Michigan Basin).

All these conventional AUs were assessed quantitatively, except for the
Precambrian Nonesuch AU, which lacked sufficient data to assess
quantitatively.

The eight continuous AUs (and associated basins) are as follows:

> Pennsylvanian Saginaw Coal Bed Gas AU (Michigan Basin),
>
> \[Devonian\] Northwestern Ohio Shale AU (Appalachian Basin),
>
> \[Devonian\] Marcellus Shale AU (Appalachian Basin),
>
> Devonian Antrim Continuous Gas AU (Michigan Basin),
>
> Devonian Antrim Continuous Oil AU (Michigan Basin),
>
> \[Silurian\] Clinton-Medina Transitional AU (Appalachian Basin),
>
> \[Ordovician\] Utica Shale Gas AU (Appalachian Basin), and
>
> Ordovician Collingwood Shale Gas AU (Michigan Basin).

Of these eight continuous AUs, only the following four AUs were assessed
quantitatively: \[Silurian\] Clinton-Medina Transitional AU, Devo­nian
Antrim Continuous Gas AU, \[Devonian\] Marcellus Shale AU, and
\[Devonian\] Northwestern Ohio Shale AU. The other four continuous AUs
lacked sufficient data to assess quantitatively.

**Resource Summary**

For the U.S. portions of the Great Lakes, the USGS estimated the
following quantities of undiscovered, technically recoverable oil and
gas resources (table 1):

> a mean value of 312 million barrels of oil,
>
> a mean value of 5.2 trillion cubic feet of natural gas, and
>
> a mean value of 122 million barrels of natural gas liquids.

These estimates are mean estimates. The ranges of uncertainty of these
estimates are shown in table 1.

**Oil and Gas Resource Allocations by Lake**

Allocated oil and gas resources were compiled for each of the Great
Lakes (tables 1 and 2). The only identified petroleum system beneath
Lake Superior is the Precambrian Nonesuch TPS, which lacked sufficient
data to assess quantitatively.

**Oil and Gas Resource Allocations by State**

Allocated oil and gas resources were compiled for each of the Great
Lakes States (tables 1 and 3). The only identified petroleum system in
the Minnesota portion of the Great Lakes is the Precambrian Nonesuch
TPS, which lacked sufficient data to assess quantitatively.

**Additional Information**

Supporting geologic studies of the U.S. portions of the Great Lakes
total petroleum systems, assessment units, and allocations are in
progress. The results of this work, as well as information on the
assess­ment methodology, are posted on the USGS Web site
athttp://energy.cr.usgs.gov/oilgas/noga as they become available.
Assess­ment results for undiscovered oil and gas resources of the U.S.
portions of the Appalachian and Michigan Basins may be found online
athttp://pubs.usgs.gov/fs/fs-009-03 and
http://pubs.usgs.gov/fs/2005/3070/, respectively. 1. 2. 3. 4. 5. 6. 7.
8. 1. 2. 3.

By James L. Coleman, Christopher S. Swezey, Robert T. Ryder, and Ronald
R. Charpentier

**Great Lakes Review Team**

James L. Coleman (Co-Task Leader; jlcoleman@usgs.gov), Christopher S.
Swezey (Co-Task Leader; cswezey@usgs.gov), Robert T. Ryder (Co-Task
Leader; rryder@usgs.gov), Ronald R. Charpentier, Robert C. Milici,
Joseph R. Hatch, Troy A. Cook, Timothy R. Klett, Richard M. Pollastro,
Christopher J. Schenk, and James W. Schmoker.

+----------+------------------+--------------------+------------------+
| **Table  |                  |                    |                  |
| 2.**     |                  |                    |                  |
| Summary  |                  |                    |                  |
| of mean  |                  |                    |                  |
| values   |                  |                    |                  |
| of Great |                  |                    |                  |
| Lakes    |                  |                    |                  |
| oil and  |                  |                    |                  |
| gas      |                  |                    |                  |
| resource |                  |                    |                  |
| all      |                  |                    |                  |
| ocations |                  |                    |                  |
| by lake. |                  |                    |                  |
+----------+------------------+--------------------+------------------+
| \[       |                  |                    |                  |
| Compiled |                  |                    |                  |
| from     |                  |                    |                  |
| table 1, |                  |                    |                  |
| which    |                  |                    |                  |
| contains |                  |                    |                  |
| the full |                  |                    |                  |
| range of |                  |                    |                  |
| sta      |                  |                    |                  |
| tistical |                  |                    |                  |
| values\] |                  |                    |                  |
+----------+------------------+--------------------+------------------+
| **Total  |                  |                    |                  |
| undi     |                  |                    |                  |
| scovered |                  |                    |                  |
| res      |                  |                    |                  |
| ources** |                  |                    |                  |
+----------+------------------+--------------------+------------------+
| **Lake** | **Oil**          | **Gas**            | **Natural gas    |
|          |                  |                    | liquids**        |
|          | **(million       | **(trillion cubic  |                  |
|          | barrels), mean** | feet),mean**       | **(million       |
|          |                  |                    | barrels), mean** |
+----------+------------------+--------------------+------------------+
| Lake     | 46.10            | 3.013              | 40.68            |
| Erie     |                  |                    |                  |
+----------+------------------+--------------------+------------------+
| Lake     | 141.02           | 0.797              | 42.49            |
| Huron    |                  |                    |                  |
+----------+------------------+--------------------+------------------+
| Lake     | 124.59           | 1.308              | 37.40            |
| Michigan |                  |                    |                  |
+----------+------------------+--------------------+------------------+
| Lake     | 0.00             | 0.112              | 1.12             |
| Ontario  |                  |                    |                  |
+----------+------------------+--------------------+------------------+
| Lake     | not assessed     |                    |                  |
| Superior | quantitatively   |                    |                  |
+----------+------------------+--------------------+------------------+
| > Total  | 311.71           | 5.23               | 121.69           |
+----------+------------------+--------------------+------------------+

+---------+-------------------+--------------------+-------------------+
| **Table |                   |                    |                   |
| 3.**    |                   |                    |                   |
| Summary |                   |                    |                   |
| of mean |                   |                    |                   |
| values  |                   |                    |                   |
| of      |                   |                    |                   |
| Great   |                   |                    |                   |
| Lakes   |                   |                    |                   |
| oil and |                   |                    |                   |
| gas     |                   |                    |                   |
| r       |                   |                    |                   |
| esource |                   |                    |                   |
| allo    |                   |                    |                   |
| cations |                   |                    |                   |
| by      |                   |                    |                   |
| State.  |                   |                    |                   |
+---------+-------------------+--------------------+-------------------+
| \[C     |                   |                    |                   |
| ompiled |                   |                    |                   |
| from    |                   |                    |                   |
| table   |                   |                    |                   |
| 1,      |                   |                    |                   |
| which   |                   |                    |                   |
| c       |                   |                    |                   |
| ontains |                   |                    |                   |
| the     |                   |                    |                   |
| full    |                   |                    |                   |
| range   |                   |                    |                   |
| of      |                   |                    |                   |
| stat    |                   |                    |                   |
| istical |                   |                    |                   |
| v       |                   |                    |                   |
| alues\] |                   |                    |                   |
+---------+-------------------+--------------------+-------------------+
| **Total |                   |                    |                   |
| undis   |                   |                    |                   |
| covered |                   |                    |                   |
| reso    |                   |                    |                   |
| urces** |                   |                    |                   |
+---------+-------------------+--------------------+-------------------+
| **      | **Oil**           | **Gas**            | **Natural gas     |
| State** |                   |                    | liquids**         |
|         | **(million        | **(trillion cubic  |                   |
|         | barrels), mean**  | feet),mean**       | **(million        |
|         |                   |                    | barrels), mean**  |
+---------+-------------------+--------------------+-------------------+
| I       | 0.75              | 0.003              | 0.14              |
| llinois |                   |                    |                   |
+---------+-------------------+--------------------+-------------------+
| Indiana | 0.82              | 0.003              | 0.14              |
+---------+-------------------+--------------------+-------------------+
| M       | 282.48            | 2.157              | 83.27             |
| ichigan |                   |                    |                   |
+---------+-------------------+--------------------+-------------------+
| Mi      | not assessed      |                    |                   |
| nnesota | quantitatively    |                    |                   |
+---------+-------------------+--------------------+-------------------+
| New     | 0.00              | 0.564              | 6.49              |
| York    |                   |                    |                   |
+---------+-------------------+--------------------+-------------------+
| Ohio    | 25.71             | 1.942              | 24.72             |
+---------+-------------------+--------------------+-------------------+
| Penns   | 0.00              | 0.552              | 6.58              |
| ylvania |                   |                    |                   |
+---------+-------------------+--------------------+-------------------+
| Wi      | 1.95              | 0.008              | 0.34              |
| sconsin |                   |                    |                   |
+---------+-------------------+--------------------+-------------------+
| > Total | 311.71            | 5.229              | 121.68            |
+---------+-------------------+--------------------+-------------------+