Note 2 - Summary of Significant Accounting Policies - Asset Retirement Obligation (Details) - USD ($)	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Balance , asset retirement obligation	$ 1,774,634	$ 1,710,677
Liabilities incurred	11,386	31,627
Liabilities settled (wells sold or plugged)	(64,129)	(22,573)
Accretion expense	47,139	46,574
Revision to estimate	5,084	8,329
Balance , asset retirement obligation	$ 1,774,114	$ 1,774,634

Amount of accretion expense recognized during the period that is associated with an asset retirement obligation. Accretion expense measures and incorporates changes due to the passage of time into the carrying amount of the liability.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)(3)
-URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849

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-SubTopic 20
-Section 45
-Paragraph 1
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Amount of asset retirement obligations incurred during the period.

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Amount of asset retirement obligations settled, or otherwise disposed of, during the period. This may include asset retirement obligations transferred to third parties associated with the sale of a long-lived asset.

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Amount of increase (decrease) in the asset retirement obligation from changes in the amount or timing of the estimated cash flows associated with the settlement of the obligation.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-Paragraph 8
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-Section 50
-Paragraph 1
-Subparagraph (c)(4)
-URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849

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Amount of a reclamation liability that is associated with a legal obligation for the closure and reclamation of oil and gas properties.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section S99
-Paragraph 1
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