Search found 650 matches

by GuyM
Sat Feb 06, 2021 4:51 pm
Forum: General Geophysics and Geoscience
Topic: The Riddle of the Great Chilean Earthquake
Replies: 4
Views: 145

Re: The Riddle of the Great Chilean Earthquake

I'm tried of theoretical discussions. I'm also not very interested in attacks on other people's opinions, for similar reasons. I'd like to see a falsifiable hypothesis, and the statistically robust experimental or modelling work done to demonstrate it's validity, rather than a theoretical refuting o...
by GuyM
Sat Feb 06, 2021 4:32 pm
Forum: General Geophysics and Geoscience
Topic: Scientists offer possible explanation for how oil and gas activity may have triggered Dallas earthquakes
Replies: 3
Views: 989

Re: Scientists offer possible explanation for how oil and gas activity may have triggered Dallas earthquakes

I'm curious as to how well the modelling from your approach matches up with the observed data when it comes to induced seismicity. The Oklahoma data would be of particular interest, as that shows a rise and then fall in monitored quakes. I'm also curious about whether your approach could be used to ...
by GuyM
Fri Feb 05, 2021 11:04 pm
Forum: Oil and Gas Exploration
Topic: Another one bites the dust
Replies: 0
Views: 56

Another one bites the dust

https://gcaptain.com/polarcus-to-cease-operations-and-terminate-all-employees/ There were some cool pictures on LinkedIn showing the ship-track from one Polarcus vessel spelling out the word "bye" Real shame - they were hugely innovative, with the Ulstein X-bow design and their commitment to low-env...
by GuyM
Fri Feb 05, 2021 11:00 pm
Forum: General Geophysics and Geoscience
Topic: The Riddle of the Great Chilean Earthquake
Replies: 4
Views: 145

Re: The Riddle of the Great Chilean Earthquake

The question to the respected geophysicists of the forum: Have I bored you with my articles on seismology yet? I think mostly the forum posts here tend to be about answering more practical applied exploration geophysics questions rather than theoretical seismology discussions; that's the majority o...
by GuyM
Wed Jan 27, 2021 3:09 am
Forum: General Geophysics and Geoscience
Topic: Thermonuclear Fusion, as a Source of Seismic Phenomena?
Replies: 16
Views: 800

Re: Thermonuclear Fusion, as a Source of Seismic Phenomena?

Therefore, if we were dealing with the natural process of radiolysis, then the radioactive background and the percentage of helium and radon would be unchanged. The data may say more gas, but that does not imply fusion. Just gas escaping from liquids under pressure, or though cracks and fault lines.
by GuyM
Tue Jan 26, 2021 3:57 pm
Forum: General Geophysics and Geoscience
Topic: Thermonuclear Fusion, as a Source of Seismic Phenomena?
Replies: 16
Views: 800

Re: Thermonuclear Fusion, as a Source of Seismic Phenomena?

So you are suggesting that Radon and Helium are a result of fusion and not nuclear decay sequences?
by GuyM
Mon Jan 18, 2021 3:28 am
Forum: General Geophysics and Geoscience
Topic: Attack of the bots?
Replies: 2
Views: 189

Re: Attack of the bots?

admin wrote:
Sun Jan 17, 2021 10:59 pm
There might be a small group of people trying to test the forum, but they don't look like bots. We certainly don't encourage this kind of posts and the situation is monitored.
That's great; just seemed a bit, well weird.
by GuyM
Sun Jan 17, 2021 7:30 pm
Forum: General Geophysics and Geoscience
Topic: Attack of the bots?
Replies: 2
Views: 189

Attack of the bots?

So - Some odd patterns in the discussion here, where a newly registered user provides the answer to an old question, sourced from another website https://detectation.com/forum/viewtopic.php?f=18&t=762&p=12951#p12951 https://detectation.com/forum/viewtopic.php?f=2&t=788&p=12950#p12950 Now I have answ...
by GuyM
Mon Jan 11, 2021 2:30 pm
Forum: General Geophysics and Geoscience
Topic: Nature and Energy of Earthquakes or Seismology for Dummies
Replies: 17
Views: 1188

Re: Nature and Energy of Earthquakes or Seismology for Dummies

To me that's the yardstick for any new theoretical or modelling approach - the modelled results from that approach have a better (statistical) fit with the observations we make. Without that you don't have a hypothesis that is falsifiable or indeed that can be tested.
by GuyM
Sat Jan 09, 2021 10:09 pm
Forum: General Geophysics and Geoscience
Topic: Nature and Energy of Earthquakes or Seismology for Dummies
Replies: 17
Views: 1188

Re: Nature and Energy of Earthquakes or Seismology for Dummies

Fully agree we haven't mastered gravity because we don't understand it; the models we have still allow us to make extensive use of gravity in exploration, whether that's sub-surface, remote sensing via satellite or sending probes to the far reaches of the solar system. In that sense the predictive m...
by GuyM
Sat Jan 09, 2021 1:57 am
Forum: General Geophysics and Geoscience
Topic: Nature and Energy of Earthquakes or Seismology for Dummies
Replies: 17
Views: 1188

Re: Nature and Energy of Earthquakes or Seismology for Dummies

Only by knowing the source of energy can the mechanism of seismic phenomena be constructed, and knowing the mechanism, it will already be possible to speak about some kind of forecast. I'm not entirely onboard with that. Mostly its the other way round - we develop some form of empirically-derived m...
by GuyM
Thu Jan 07, 2021 2:05 am
Forum: General Geophysics and Geoscience
Topic: Nature and Energy of Earthquakes or Seismology for Dummies
Replies: 17
Views: 1188

Re: Nature and Energy of Earthquakes or Seismology for Dummies

"If we admit that earthquakes cannot be predicted, then we will have to resign and admit the fact that we have spent many years on a chimera. Do we need this? No! Therefore, we will tear with our teeth everyone who goes against us." That's not really how science works where I am! You only have to lo...
by GuyM
Thu Jan 07, 2021 1:58 am
Forum: General Geophysics and Geoscience
Topic: Nature and Energy of Earthquakes or Seismology for Dummies
Replies: 17
Views: 1188

Re: Nature and Energy of Earthquakes or Seismology for Dummies

Remember, earthquake prediction is impossible !!! I don't know any seismologists who claim to be in the quake prediction business; forecasts and models, perhaps, but not predictions. Liej the meteorologists, they choose their words carefully and with good reason - eyes on what happened in Italy. Wa...
by GuyM
Fri Jan 01, 2021 4:32 pm
Forum: General Geophysics and Geoscience
Topic: Nature and Energy of Earthquakes or Seismology for Dummies
Replies: 17
Views: 1188

Re: Nature and Energy of Earthquakes or Seismology for Dummies

I've imaged the subducting tectonic plate that eventually pushes under my house. Sometimes that plate gets stuck, until it jumps free. Sometimes hydrothermal fluids in the subducting slab force themselves upwards under pressure. Sometimes there are slow-slip events that reduce the stress. That's all...
by GuyM
Fri Jan 01, 2021 3:51 pm
Forum: General Geophysics and Geoscience
Topic: Thermonuclear Fusion, as a Source of Seismic Phenomena?
Replies: 16
Views: 800

Re: Thermonuclear Fusion, as a Source of Seismic Phenomena?

I'm unsure what you mean by "trust these numbers"? Every measurement - direct or indirect - has a limiting accuracy based on a range of constraints, and velocity analysis is no exception. Manual analysis is one thing, however when you start to get into semi-automatic high density velocity analysis t...
by GuyM
Fri Jan 01, 2021 12:02 am
Forum: General Geophysics and Geoscience
Topic: Thermonuclear Fusion, as a Source of Seismic Phenomena?
Replies: 16
Views: 800

Re: Thermonuclear Fusion, as a Source of Seismic Phenomena?

"Everything that we know from the results of testing rock samples should be forgotten like a bad dream because we can apply Young's modulus only to isotropic samples of small size." Well, we see the self-same issues with measuring seismic velocities from core (or using sonic logs) and the velocity d...
by GuyM
Thu Dec 31, 2020 7:13 pm
Forum: Oil and Gas Exploration
Topic: Meaning of "X = NOTHING Y = EASTING"
Replies: 2
Views: 188

Re: Meaning of "X = NOTHING Y = EASTING"

Hopefully it says NORTHING rather than NOTHING? Normally you would have X as the EASTING coordinate and the Y as the NORTHING; maps usually have north pointed along the Y-axis. That's a left-handed dataset - if you hold up your left hand and stick out your forefinger and thumb in an L shape, then yo...
by GuyM
Thu Dec 31, 2020 7:02 pm
Forum: General Geophysics and Geoscience
Topic: Thermonuclear Fusion, as a Source of Seismic Phenomena?
Replies: 16
Views: 800

Re: Thermonuclear Fusion, as a Source of Seismic Phenomena?

"terrestrial rocks are incapable of storing mechanical energy"

Can you expand on this in terms of the what we know about elastic moduli of rocks from both rock physics laboratory measurements and modern exploration seismology?
by GuyM
Mon Dec 28, 2020 8:56 pm
Forum: General Geophysics and Geoscience
Topic: constant velocity model
Replies: 3
Views: 659

Re: constant velocity model

Sure, but in seismic data processing it usually means that we are assuming that the p-wave (and possibly s-wave) seismic velocity of the Earth is constant. That's not a great approximation, however it can be useful under some circumstances, especially when developing or testing algorithms.
by GuyM
Mon Dec 28, 2020 8:53 pm
Forum: General Geophysics and Geoscience
Topic: meaning of redundancy
Replies: 6
Views: 931

Re: meaning of redundancy

Data redundancy is a data organization issue that allows the unnecessary duplication of data within your database. A change or modification, to redundant data, requires that you make changes to multiple fields of a database. While this is the expected behavior for flat file database designs and spr...
by GuyM
Fri Dec 11, 2020 6:40 pm
Forum: Oil and Gas Exploration
Topic: Flat and floating datum corrections, why and when?
Replies: 6
Views: 781

Re: Flat and floating datum corrections, why and when?

So, the geophysics does not have a bright future apparently, right? In real (inflation adjusted) terms oil prices are about where they were for the first decade of my career ('92-'02); the industry was small and lean then, with redundancy rounds and company failures common. The root cause was over-...
by GuyM
Fri Dec 11, 2020 3:54 am
Forum: Oil and Gas Exploration
Topic: Vibroseis seismic data processing
Replies: 4
Views: 660

Re: Vibroseis seismic data processing

Well if you wanted to collect data to a maximum depth of 3 seconds with a 6 second sweep, you'd need to record for a total of 9 seconds.
It's pretty usual to give all of the acquisition parameters even of the data has been deconvolved already..
by GuyM
Fri Dec 11, 2020 12:57 am
Forum: Oil and Gas Exploration
Topic: Vibroseis seismic data processing
Replies: 4
Views: 660

Re: Vibroseis seismic data processing

Looks to me like the data is already correlated; its usual to get the data with the correlation already applied.
The record would be a lot longer if it was uncorrelated - you'd have the target record length plus the sweep length.
by GuyM
Fri Dec 11, 2020 12:55 am
Forum: Oil and Gas Exploration
Topic: Flat and floating datum corrections, why and when?
Replies: 6
Views: 781

Re: Flat and floating datum corrections, why and when?

I was on the software development side of things for a long time; we were working using agile approaches for a decade or so and there's plenty of work in that domain. I'm currently working as a Scrum Master - less on the software development side and more in general IT. Working with a a couple of te...
by GuyM
Wed Dec 09, 2020 8:22 pm
Forum: General Geophysics and Geoscience
Topic: Sub bottom profiling - lakes / rivers
Replies: 1
Views: 581

Re: Sub bottom profiling - lakes / rivers

Done some stuff on lakes where we digitised the seafloor, then smoothed it (low pass spatial filter) You can then calculate a static shift from the smoothed and original profiles to apply to the data; one way is to: - extend the data by 500ms - shift the data down by 500ms - shift the data up by the...