Very Low Frequency Electromagnetic (VLF-EM) data interpretation using Karous-Hjelt software

This tutorial explains how to use the KHFFILT program (Karous-Hjelt filter software) to perform Karous-Hjelt and Fraser filtering on geophysical Very Low Frequency (VLF) data. VLF-EM data may be used for environmental geology, groundwater, and mineral exploration studies.
#Karous-Hjelt
#Fraser filtering
#VLF measurements
#VLF-EM
#vlf
#KHFFILT

[@karhukivi]

It is important to know the host rock resistivity and input that as skin depth (approximately 3.5 x sqrt(resistivity) ). This will place a realistic limit on the depth extent of the conductor in the KH diagram. A high resistivity host rock not only increases the skin depth ( i.e. depth of investigation, but also increases the in-phase response. In areas of low host resistivity e.g. tropical weathering, clays etc., the skin depth might be only 10-20 metres and a more conductive target will not be detected beyond about 1.5x times that depth, perhaps 30m maximum.

[@judeejepu]

@@karhukivi Thanks for your input. This is well help in future interpretations

[@anthonychukwuemekaejepu7499]

Wow 😯 this is interesting and helpful 👏🏽👏🏽👏🏽

[@judeejepu]

Glad you think so!

[@karhukivi]

If your field survey was facing left to right, in the direction of increasing station numbers, then you should reverse the sign, the Fraser filter is a maximum over the conductive zone which is shown in blue, instead of the more conventional red. The synthetic data shown first, is clearly facing left to right.

[@judeejepu]

Thank you for your input. Your observations are noted.

[@khushwantmistry1031]

Sir, knowledgefull video , you have use two data , 10 meter interval horizontal distance, but second data unit not mentioned , I want konow what is unit second data coloum please describe 💐🙏

[@judeejepu]

Please can you add more details to your query?

[@judeejepu]

Ok. I understand. The VLF machine used receive frequency in different frequency ranges. So other columns contain measurements in other frequency bands. Hope this is helpful.

[@geophysic5830]

thank you

[@judeejepu]

You're welcome

[@khushwantmistry1031]

Thank for reply , Stil I am not satisfied, out put data that measured by machine in which form ?as in second column data -33.4,29.1,26.1....so on , what unit of this numbers? Sir please also mention which machine used to measure the , please share name and model of machine

[@judeejepu]

Contact me via email geodiscoverygeosciences @ gmail . com

[@glovis-gis]

GREETINGS TO YOU...I FIND YOUR VIDEO TUTORIALS VERY INTERESTING. PLEASE HOW CAN I GET THE KARUS SOFTWARE OR KINDLY SHARE ME A LINK TO DOWNLOAD THE SOFTWARE

[@judeejepu]

send an email to judeejepu @ outlook.com. I will then send it to you. Best regards

[@edgarmastache1024]

@@judeejepuhello im interesting in the software could you send me it please? Regards

[@judeejepu]

@@edgarmastache1024 send your me a mail at judeejepu@ outlook.com

[@adil101964]

i also want this software , can you help. Thank you

[@judeejepu]

Thank you for watching the video. Send an email to judeejepu @ outlook.com. Do not forget to like and subscribe. Thanks

[@ayodejigabriel6757]

Thanks for this but can i get the software sir?

[@judeejepu]

Send an email to geodiscoverygeosciences @ Gmail(dot)com. Do not forget to subscribe. Thanks

[@ayodejigabriel6757]

Okay. Thank you

[@geophysic5830]

please share with me data

[@judeejepu]

Send email to judeejepu @. gmail. .com