<div dir="auto"><div data-smartmail="gmail_signature" dir="auto">Hi all .</div><div data-smartmail="gmail_signature" dir="auto">As you know , we usually  extract some informations from landsat . For instance , lineaments , alterations , etc.</div><div data-smartmail="gmail_signature" dir="auto">So I want to know , what is the maximum depth undeground the above-mentionned informations are collected ? </div><div class="gmail_quote" dir="auto"><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div><blockquote type="cite"><div dir="ltr"><div><br>
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