Property, Plant and Equipment

12 Months Ended

Dec. 31, 2021

Property, Plant and Equipment [Abstract]

Property, Plant and Equipment

Property, Plant and Equipment

	As at December 31,
(Thousands of U.S. Dollars)	2021		2020
Oil and natural gas properties
Proved	$	4,302,473	$	4,106,768
Unproved	131,865		161,763
	4,434,338		4,268,531
Other (1)	34,943		32,135
	4,469,281		4,300,666
Accumulated depletion, depreciation and impairment	(3,473,484)		(3,336,184)
	$	995,797	$	964,482

(1) The “other” category includes $13.9 million right-of-use assets for operating and finance leases which had a net book value of $3.9 million as at December 31, 2021 (December 31, 2020 - $11.4 million which had a net book value of $4.4 million).

Depletion and depreciation expense on property, plant and equipment for the year ended December 31, 2021, was $135.7 million (2020 - $160.8 million; 2019 - $220.8 million). A portion of depletion and depreciation expense was recorded as oil inventory in each year.

Unproved Oil and Natural Gas Properties

At December 31, 2021, unproved oil and natural gas properties consist of exploration lands held in Colombia and Ecuador. Unproved oil and natural gas properties are being held for their exploration value and are not being depleted pending determination of the existence of proved reserves. Gran Tierra will continue to assess the unproved properties over the next several years as proved reserves are established and as exploration warrants whether or not future areas will be developed. The Company expects that approximately 100% of costs not subject to depletion at December 31, 2021, will be transferred to the depletable base within the next five years.

The following is a summary of Gran Tierra’s oil and natural gas properties not subject to depletion as at December 31, 2021:

	Costs Incurred in
(Thousands of U.S. Dollars)	2021		2020		2019		Prior to 2019		Total
Acquisition costs - Colombia	$	—	$	—	$	—	$	10,268	$	10,268
Exploration costs - Colombia	2,416		9,909		36,881		63,306		112,512
Exploration costs - Ecuador	2,708		2,160		4,217		—		9,085
	$	5,124	$	12,069	$	41,098	$	73,574	$	131,865