Drilling an Oil or Gas Well  

(There Are Five Steps)

And the Geologist Wears a Different Hat for Each of Them! 

Step 1 - Prospecting -- (Geologist = Scientist)

"Prospecting" is the process the geologist goes through to locate a place to drill a well.  Most petroleum geologists work in an office, where they have access to well logs, core records, drilling records, and other data that they need to work.  They construct maps and cross-sections to help them locate the best places to drill wells.

The geologist is interested in anything that happens in his area, particularly news of new discoveries by other companies, success producing hydrocarbons from a previously-untested zone, and any drilling activity that is close to his leased acreage.    If he sees a promising new area, he will recommend to his Land Department that they attempt to lease the acreage.  

He studies his maps and cross-sections and runs computer simulations that help him select the next best location to drill.  He is always thinking about the next drilling location!  This is the primary job of the Petroleum Geologist.  The geologist will want to know what type of trap he is dealing with, and the composition of the sedimentary rocks he will be drilling through.  He wants to estimate the porosity of his prospective "pay zone", and know whether or not he can expect to encounter very high pressure in the hole.  If seismic is involved in the prospect, he will consult with the geophysicist and get his opinion of the prospect.

When he has finally found the correct spot, he spends much time cross-checking to ensure that he has not missed anything.  He wants to make sure that he is not "surprised" later by finding out that his location was drilled by another company 30 years ago (and was dry), discovering that his company has no legal right to drill on the location (lease problems), that the well has been drilled in the wrong place (it happens!), or that faulting or other geologic conditions (or plain old human error) will not spoil his prospect. 

Step 2 - Packaging -- (Geologist = Artist/Designer)

The geologist has huge amounts of data available that he has used to define and select his prospect.  Now, he must condense this data into a set of presentation materials that can be shown to non-geologists in the oil business.  These people may include managers, investors, bankers, engineers, or others who will help to approve and get financing for the drilling deal.  

If the geologist works for an oil company, these people will usually be fellow employees of the business.  If he works for himself (as an "Independent" geologist), various people unrelated to each other may be involved.  In any case, his objective is to condense his work into a form that be easily and quickly understood by many people from different backgrounds.  

For this task,  he may prepare sets of simplified maps and cross-sections, often highly-colored and attractive to the eye.  He may package his deal using Powerpoint, or other presentation software.  But the objective  is to produce a set of useful reference materials he can present and demonstrate to others involved in the project.  Creativity, design sense, and art skills are very important during this phase.  He also needs to anticipate all questions, and be prepared to answer every one of them.  He must be very sure of himself and his facts before he moves to the next step.

Step 3 - Selling the Deal -- (Geologist = Salesman)

Now the geologist must step into a role that is sometimes foreign and often uncomfortable for him ... selling his prospect.  This is because geologists are scientists, with scientific backgrounds and schooling.  They are used to talking to other scientists.  But now the geologist must sell the deal to other people who are not geology experts or scientists.  

He is looking to convince others that his prospect is worth drilling, that investors will get a good return on their money, and that the financing they provide for the deal will be money well-spent.  Don't forget that even an inexpensive test well can cost more than a million dollars, and some exploration tests may easily run into tens of millions!  So the geologist wants to be sure of his facts, and everyone else involved must believe that the well has a reasonable chance of being successful.  

If he works for an oil company, the geologist will meet with the landman, who will ensure the company has the legal right to drill the well.  He will consult with the engineer, who will determine the (nearly) exact cost of drilling the well, and recognize any special drilling problems that might develop.  Marketing personnel will ensure that the company has a market (buyer) for the oil, or a pipeline for the gas.  Managers, responsible for ensuring that the company's drilling budget is spent wisely, will also approve the well.  If outside financing will be used, the geologist will go over the prospect with representatives of the bank or other individuals or partnerships putting up the money.  

When he's done, the geologist will have "sold" his prospect to anywhere from a few to several dozen people.

Step 4 - Drilling -- (Geologist = Supervisor)

Next comes the part that every geologist enjoys the most!  Drilling the well!  It has now been several months since the geologist started working on his idea...which then became his prospect.  Now the surface owners have been paid, permits acquired, the money raised, roads and drilling location built, pipe and supplies ordered, and the company has engaged a drilling contractor who owns the drilling rig, and will drill the well in the manner specified.  The contractor will often select the type of drill bits to be used that his experience tells him will work best, hire a crew, and make other decisions concerning the drilling.

Drilling a well is a very complex procedure involving many people where nearly everything must go right, and there is no room for error.  Dangerous and powerful machinery, bad weather, and mechanical failures must be faced daily. The work goes on for weeks to months, 24 hours a day, nonstop.  A slip-up at any point can ruin the expensive hole, cost a fortune, get people killed, or all three.  

The geologist will closely monitor all aspects of the drilling as it takes place.  He will hire a mud logger to "sit" the well day and night, study the well cuttings,  report shows of oil and gas, and keep track of other things on the location.  The geologist will monitor the formation tops as they are encountered and discuss the progress of the drilling with the investors.  The geologist will decide where and when to takes cores or DST's.  When the hole has been drilled,  the geologist will select a logging company and the proper logging tools to evaluate the hole.  Finally, when the well is logged, he will examine the logs and recommend that the well be either completed or plugged.   

Step 5 - Completion -- (Geologist = Advisor)

The job of completing the well is mainly in the hands of the petroleum engineer.  He will decide what type of casing to run, what type and method of cementing will be used, and design and implement the completion procedure itself (which may involve perforating, breakdowns, acid jobs, or fracs),  However, he will depend on the geologist at this time to advise him at each step of the way.  To start, the geologist will give the engineer a list of formation tops and tell the engineer which zones will be tested.  

The geologist is usually the person most familiar with the area and the practices of other oil companies.  He may suggest a certain style or method of perforation, or offer advice on cementing techniques.  He may be familiar with the most successful fracturing or breakdown procedures in the area.  He will relay this information to the petroleum engineer, who will usually be thankful for the help!  Working as a team, the geologist and petroleum engineer will get the well completed and put it to work making money for the company.