₦airaland Forum

Sorry for being away all ds while, been seriously occupied. If you will like to meet the management staff of Dextol Global Geophysicals, you can connect with us at the on going conference of the Nigerian Association of Petroleum Explorationist at the University of Ìbàdàn.
Thanks.

ollypapi:
yeah... nice one my guy... tested and trusted

thanks boss.

msogunro:
Looking forward to the discussion.


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Please do not put up the map with the exact location of my site. Thank you

oh, noted sire!

The curve from the geophysical survey done at Adegbayi area is shown below.

The curve depicts changes in lithology with depth. You can see its very different from the curves obtained from lime stone and sand/shale terrain. This particular one revealed up to five layers. The topmost layer is clay followed by lateritic soil, then we have the weathered basement rock and fractured basement following. An open pit on the site was utilized in getting some of these information.

While drilling this point, we are expected to meet some fractures at 40m and around 80m.

From the images from the pit, we can see some form of sediment layering depicting the geology of the area. Don't let me go in that direction

Now coming to basement terrain, I will be citing examples from works from Abẹ́òkúta and ibadan.

Will be using Nairalanders' site.... msogunro at Adegbayi area and one other person at Moniya area.

Larwin:
Cont.



In this area, there has been series of report of collapsing of borehole, so Dextol Global Geophysicals was called in to come and investigate.

From the investigation, we found out that the whole area, has been tapping water from the same aquifer at around 40m(as seen in the curve) thereby imposing so much pressure on the sediments and consequently loosing up and After a short while caving in.

After the investigation, our advice was to go deeper and tap from another aquifer unit which is at 100m or tap from the aquifer at 40m but with good completion.

Am so sorry for the slow update. Man is very busy.

Now tapping water at depth of about 100m, I hope you know 150k or 200k might not work here if you really want a good job.

Some ppl will tell you some guys do it for 120k and why is your own high like this.

Some people will even tell you not to bother conducting geophysical Survey.....

n3xt:
Good job.

cc mynd44

Thanks n3xt

Yeah, the person is right. If your ready to drill call me and let's discuss 08060288869.

I represent Dextol Global Geophysicals.
You can check my thread here

https://www.nairaland.com/3236298/know-geophysical-investigation-borehole-drilling

Shegman22:
Nice work here Larwin. I believe people are getting more enlightened.

cc lalastica.

Thanks Shegman22, u mean Lalasticlala

pseudomonas:
the couch of the foundation was eventually increased to four. Though the area isn't water logged this is just to be sure the building is higher than the road network and the drainage if eventually the govt decides to do that.

Good thinking, right decision. Well done Op

Larwin:
here is the result from the depth sounding. You can see the alternation of sand and clay clearly from the curve.
will continue tomorrow to talk more on this. got to rest.

Cont.



In this area, there has been series of report of collapsing of borehole, so Dextol Global Geophysicals was called in to come and investigate.

From the investigation, we found out that the whole area, has been tapping water from the same aquifer at around 40m(as seen in the curve) thereby imposing so much pressure on the sediments and consequently loosing up and After a short while caving in.

After the investigation, our advice was to go deeper and tap from another aquifer unit which is at 100m or tap from the aquifer at 40m but with good completion.

bplenty:
Thanks a great deal @larwin, iwo ni ire kan o. she amin adura.

Lols, amin ooo.... Thanks Bro. Your house don feature here on my thread here o
https://www.nairaland.com/3236298/know-geophysical-investigation-borehole-drilling

bplenty:
@Larwin

Off course you shall be able to recognize the house. It's just gone through a lot of remodeling ni.

Honestly am happy for this, just smiling where I dey here.

Oops, I hope I will b able to recognize ds building a
gain.

here is the result from the depth sounding. You can see the alternation of sand and clay clearly from the curve.
will continue tomorrow to talk more on this. got to rest.

Hi peeps, permit me to continue with my previous discussion.

We have talked about drilling in a limestone terrain and we have seen a typical curve from the area.

Now let's go to Lagos where we have sand-shale(clay)-sand repeating downward till you meet basement rock.

Here, our target is the sand unit because it's porous and permeable(it doesn't hold water, it allows it to pass freely).

So why do we need geophysical Survey here.... The survey will guide you so as to know the depth you are going and also to pick the best aquifer for your client.

I will post a typical curve from a geophysical survey carried out at Greensrich School, along Ikorodu high school.

msogunro:
What is your email address?

What determines the 20k-50k charge? I would like to know the price for this in Ibadan.

call 08060288869

There is a land behind Nigerian brewery ife road, about 2 and half plot. We need to sell it so as to raise money for a pressing need. You can contact me for more details.

Larwin:
From the curve, at about 35m, you can see the curve plunging downward with extremely low resistivity. That is typical of a limestone terrain.
The knowledge of geology of the area aided in this interpretation tho.

The geoelectric section explains it further.

So how do you drill in this kind of terrain

We all know what limestone is (some people prefer to call it Calcite), nobody want to be drinking water full with carbonates due to its health effect. So while drilling in this area, it's either the drilling terminate before reaching the limestone layer or you have to drill pass the limestone layer. But in this case, we are drilling pass the limestone layer.

So while drilling, there is need to stabilize the wall of the hole so it won't collapse and also to bring cuttings back to the surface because we don't want limestone contaminating the water. We all know limestone is soluble in water. So in doing this some polymers is added to the drilling mud so as to make it thicker. These polymers serve as stabilizer and prevent the wall of the hole from collapsing down.
After the drilling is completed, these polymers are later remove by pumping water out with great pressure.

This is another reason while you must not patronize quacks or look for cheap borrows. Just consult an organization with great reputation so they can guild you right.

As clients seeking the service of any of these;

one quick way to sense quarks is their charges - most times, they give very low charges compared to probably the usual market price (I'm as well not in support of outrageous prices) basically because they really do not have the interest of the job at heart but just want to get the job and get their own and leave, not minding their image or future opportunities. Then, they get to use substandard materials and do the job anyhow, some people would even run away after collecting money (just speaking my mind anyway).

Another way of avoiding quacks is to contact registered companies or persons who have sound knowledge in the desired area, even if the person cannot offer the service, such would guide and help recognize the right person for the job. Registered ® companies are always mindful of public image even more than money.

Previous projects - this is another way of avoiding quarks, clients may need to ask the intended company or persons about how they have delivered in such capacities in the past, if competence is proved, the client can go ahead with the project.

To your last question, "YES" - Geophysical investigations would give an idea of the drilling depth that is ideal for a particular site or location. Geophysical investigation also has its applications in foundation studies and other engineering studies. This is the next aspect I intend to shed more light on after trashing the borehole and water well issue, I intend to share my personal fields experiences in the post as well.

Thanks.

@msogunro, thank you for the compliments. I am so sorry for responding ds late, been busy with projects.

The cost for geophysical investigations varies from place to place and projects, however, our range as a company falls within 20k - 50k. Sometimes we go as far as integrating various geophysical methods in prospecting for our desired interest in the Subsurface. You can inbox me privately for more clarifications or deals.

"Quacks" as a subject is the problem of every profession here in Nigeria except if we only want to hide from the truth, our industry is not exempted in this as well. The resultant effect of their involvement have led to the increased Failures that is being observed everywhere, although their pricing or quote is always luring especially to clients that would always want to cut costs.

There are Associations and bodies governing the profession some of which are;

Nigerian Mining and Geosciences Society (NMGS) - Headquarters in Jos, plateau state.

A governing council that overseas exploration works and related studies is:

Council of Mining Engineers and Geosciences (COMEG) - they are also saddled with the responsibility of controlling quacks and ensuring competence in various exploration works. COMEG issues a seal or certification to operate as a mining engineer, Geoscientist and related fields.

abimbawealth:
Larwin, your attention is needed!!!

Thanks swt

Wow, nice work

tunazee:
Considering the rate at which people are drilling boreholes in their houses as a means of accessing portable water in this country, is there any threat to the underground water reserve? Is there any law or regulation guiding bore hole drilling because it seems to be the order of the day?

Wow, what a question. Well we just have to thank God for where he put us. Naturally there is no threat to the reserve, but tapping the reserve could pose a threat.

Nigeria is situated on a stable plate(not active) which means we r still safe. I don't want to go too technical here.

But Those on the sedimentary terrain like Lagos are likely to encounter something like subsidence in the nearest future if the indiscriminate drilling of holes continues.

So far there is no law guilding drilling in Nigeria. We only have associations

tushantuna:
The construction of my house is at roofing level, few weeks ago a water survey on my land shows that the borehole will be dig inside the sitting room which i found it difficult because i cant pulldown what have laboured alot to construct. My question goes thus,what can i do to have a maximum water supply without destroying my sttucture ?

This is very funny, well this is part of the reason we always advice builders to do the survey first.
Am very sure there will be another point you can drill. Although this might be difficult to locate due to probably obstructions from development that has taken place.
What you need is a more detailed study and even integration of methods to get a more desired point. This might cost you more. You can pm me, we ll guide you right.

Hardeybiryo:
Op, why does some boreholes produce dirty water?

dirty water is usually due to poor completion of a hole.
It happens majorly in two ways.... surface materials getting into the hole or lose sediments infiltrating into the hole.

Poor completion ranges from grouting to casing and installation of pump.

If these three are not done properly then there is high possibility of getting a dirty water.

Grouting is a critical step in borehole completion. It's function is to prevent surface infiltration or Pollution and at the same time prevent the already weaken wall of the formation from caving in. It's done using cement or gravel packing. Different field warrant different use.

Casing is also another issue, the types of casing u use depends on yr hole condition and geology.

And the use of pump is a function of the hole pressure and yield. If your pump is too powerful than what it suppose be, it will at a time weaken the formation your tapping water from and in the long run you will be seeing sediments in your water.

This is the reason why we at Dextol Global Geophysicals always advice our potential clients not to look at the cost they will spend on getting a borehole but to look at the professionalism and honesty.
Looking for cheap borehole is just like looking for poor hole completion.

Even your hole might not be properly cased down where the need be. People just have to wake up and stop falling victims. Pay a standard price and you will get a standard hole. It's not always about getting water, it's about your hole serving you and lasting without any problem.

Thanks

sholaw:
Thanks for the clarity, and am so impressed with this. I hope with your help I'll be able to increase my output.

Yes sholaw, I will pm you now. It will be good to partner with you.

Here is another technology from our partner in the USA

It's called LandMapper.

@sholaw, that's a great question. Am not expecting it any sooner tho.
I have it in mind to talk bout it later so as not to derail from borehole aspect. But now I have to say it.

There is an aspect of geophysics we called agro-geophysics. It's presently in use in countries like Israel, USA, Russia... Only few Nigerians understand its worth and some of them have applied it on their farm.

This new technology helps in checking variations in soil properties rapidly thereby reducing the amount of samples being sent to the lab and so saving cost. It helps you to get a well detailed sampling plan for your farm.

Even with it you might not need further laboratory testing.

The farms we have carried it on are experiencing great and even yield right now.


Attached is a land being prepared for farming.

abimbawealth:
Na ma na...abi


Look for you? You lost?

I go get u for street.

abimbawealth:
You wan find am go house

If I find am go shey e bad ni... U sha no look for me