Kačák Event
... that the Kačák Event caused widespread marine anoxia, forming black shales such as those that generate gas in the Marcellus Shale?
... that the <b id="mwCCU"><a href="./Kačák_Event" id="mwCCY" rel="mw:WikiLink" title="Kačák Event">Kačák Event</a></b> caused widespread <a href="./Anoxic_event" id="mwCCc" rel="mw:WikiLink" title="Anoxic event">marine anoxia</a>, forming <a class="mw-redirect" href="./Black_shale" id="mwCCg" rel="mw:WikiLink" title="Black shale">black shales</a> such as those that generate gas in the <a href="./Marcellus_Formation" id="mwCCk" rel="mw:WikiLink" title="Marcellus Formation">Marcellus Shale</a>?