Mexico started the calendar in January with a round that attracted $93 billion in investment pledges and followed with another securing over $8 billion. In March, Brazil drew $2.4 billion in pledges for offshore areas on top of about $30 billion from an October bidding round.

The following is a list of expected bidding rounds in each country this year:

MEXICO A July onshore round will allocate up to 37 areas, followed by nine unconventional blocks, with results due in September. Mexico also hopes to schedule an auction of heavy oil areas in the Gulf's shallow waters late this year.

BRAZIL

Brazil will host another large offshore auction this year and the government is preparing the transfer of rights from state-run Petrobras (>> Petroleo Brasileiro SA Petrobras). The country plans a permanent offer of up to 850 onshore and offshore blocks starting in May, a number that could climb to 1,700 areas in 2019.

The South American country, which is reducing royalties for bordering and mature fields, has worked hard in recent years to relax its local content rules, an issue seen in the past as a major obstacle on investment.

COLOMBIA

In May, Colombia expects to begin offering up to 25 onshore and offshore blocks in a permanent auction similar to what Brazil is planning, a process that will follow its Sinu-San Jacinto round including 15 areas to be awarded in early April.

The country's regulator also is in talks with holders of nine permits for seismic studies in the Caribbean Sea to convert them into exploration and production contracts.

URUGUAY

Results of third offshore round could be disclosed in late April, including 17 blocks for exploration and production at its Exclusive Economic Zone.

The nation is offering less demanding qualification conditions and mandatory exploration terms, according to the government.

PARAGUAY

State-run Petroleos Paraguayos plans to relaunch in the second quarter an auction to find partners for two exploration and production areas after a failed attempt last year.

The blocks - Petropar III and Palo Santo - are part of five areas received by Petropar to be developed in Paraguay's western zone near the border with Bolivia and Argentina.

ARGENTINA

Argentina will appear late in Latin America's 2018 auction wave with terms of its first offshore round due in July and results expected in December.

The auction, of a mostly unexplored area covering 225,000 kilometers off the Atlantic coast, does not include bidding bonuses, according to the government. Interested firms can propose blocks to be added to the offer.

(Reporting by Marianna Parraga; additional reporting by Daniela Desantis in Asuncion, Paraguay and Neil Marks in Georgetown, Guyana; Editing by Gary McWilliams and Brian Thevenot)