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Passive electro-optical imagers in orbit like Landsat have no penetration ability into ground or vegetation. It only measures the very top surface properties. There is well understood water penetration in the visible bands, primarily the blue band, and there
are several articles in the literature. If you wish to actually penetrate soil you need to move into the microwave (radar) bands, and even there, it is severely attenuated by moisture and only works in very dry areas, also well describes in the literature.
Ground penetrating radar dragged by sleds on the ground do have very good penetration generally, but not from airborne or satellite sensors.
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<div class="">I hope this helps,</div>
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<div class="">Scott Madry<br class="">
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<div class="">On Jan 11, 2022, at 2:16 PM, jean Lukusa <<a href="mailto:lukusam@gmail.com" class="">lukusam@gmail.com</a>> wrote:</div>
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<div data-smartmail="gmail_signature" dir="auto" class="">Hi all .</div>
<div data-smartmail="gmail_signature" dir="auto" class="">As you know , we usually extract some informations from landsat . For instance , lineaments , alterations , etc.</div>
<div data-smartmail="gmail_signature" dir="auto" class="">So I want to know , what is the maximum depth undeground the above-mentionned informations are collected ? </div>
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