A mismanaged and corrupt Nigerian oil and gas industry doesn't sound like a great place to invest. A report last year commissioned by the country's oil minister in the wake of fuel protests found just that, and more than £20bn was lost in the country in the last decade from oil theft and gas price fixing. So not the best country to drill for oil perhaps? Afren begs to differ.

On a quiet day for reporting in the City, investors will focus on the hunt for African oil. Mid-cap index oil explorer Afren will update on trading.

It has been stepping up oil production offshore from Nigeria, and investors will want to know how this is going. But punters have been concerned about its operations in Kurdistan, a risky area in which to operate that has been hit by political quarrels over the export of oil. Despite this, Morgan Stanley rates the stock overweight, or buy, and earlier this month raised its target price to 220p.

The oil sector has been the subject of bid rumours for months, with BG Group said to be a target, and some deal-hungry advisers have also mentioned Afren as a possible recipient of interest. But for now the group will be concentrating on stepping up production volumes and adding cash to its pile, which stood at more than $780m (£487m) in November.

Results/Updates: City of London Investment Group.

Tomorrow

London's stock exchange might seem a funny place for a Mexican silver miner. But Fresnillo happily nestles in the benchmark index alongside Russians, Kazakhs, South Africans and Ukrainians. Tomorrow it will reveal its fourth-quarter output. Its shares were this month hit by a fall in the silver price, and analysts at UBS cut their rating of the stock. But the silver price picked up last week and experts suggest the global economic outlook should push the it up further. Fresnillo has previously said it is on track for an annual output of 41 million ounces.

Better economic conditions have been helping beer maker SABMiller too. Analysts at Berenberg Bank expect sales growth will "probably continue to be robust" at around 5 per cent.

Results/Updates: Cairn Energy, Optos.

Wednesday

Investors were unsettled when those cads at the Office of Fair Trading decided last week that they needed a bit longer to look at Britvic and AG Barr's £1.4bn merger. Did the OFT have a particularly heavy new year? Maybe it should have stuck to Irn-Bru. Rather than decide by the end of the month, it now has until 13 February. Britvic will report on its first-quarter trade, and investors will be hoping the pain caused by its Fruit Shoot recall and the wet summer will be behind it.

Results/Updates: Abcam, BHP Billiton, Biome Technologies, Close Brothers, Findel, Hochschild Mining, Land Securities, Sage, WH Smith, Unilever.

Thursday

Defence contractor Chemring has been through it all – a collapse in demand, a new chief executive, takeover talks that came to nothing and a share price that has been consistently travelling in the wrong direction. New broom Mark Papworth, who joined in October, will present his strategic plan at the results on Thursday. Shareholders are hoping for better news in 2013.

Some traders still think Chemring could be a takeover target – Carlyle walked away in November – but any new suitor will wait until after the results. Analysts at Investec Securities reckon underlying pre-tax profit will have slumped 41 per cent to £70.8m in the latest two-month trading period. But the market knows the numbers will be bad, so it will be all about what Mr Papworth has to say. UBS analysts call it an "exciting restructuring story", and rate the shares a buy with a 360p share price target.

Results/Updates: APR Energy, easyjet, Emis, Fuller Smith & Turner, First Group, Carphone Warehouse, Invensys, London Mining, London Stock Exchange, Paypoint, St James's Place.

Friday

There is a new boss and a new strategy at mining giant Anglo American. Chief executive Mark Cutifani will start in April but Anglo has already embarked on a plan. It has outlined ideas for a strategic review of its South African platinum mines. Analysts at HSBC described the move as "a pragmatic, detailed and courageous plan." The group will update on production on Friday, and some analysts think it could be time to buy the shares as they lost more than 7 per cent last week.

Results/Updates: Brooks Macdonald, William Hill.

Economics Diary

Today

CBI.

Tomorrow

UK public-sector borrowing, CBI trends – total orders, selling prices, CBI Business Optimism Survey.

Wednesday

World Economic Forum annual meeting, unemployment data, average earnings, Bank of England Monetary Policy Committee.

Thursday

British Bankers' Association house purchase loans, CBI reported sales, US unemployment claims.

Friday

UK fourth-quarter GDP.