Tafkin Monoun wani tabki ne da ke Lardin Yammaci, Kamaru, wanda yake a yankin Oku Volcanic. A ranar 15 ga Agusta, 1984, wani ɓarnar ɓarkewa ta auku a tafkin, wanda ya haifar da sakin adadin carbon dioxide mai yawa (CO2) wanda ya kashe mutane 37. Da farko, mutuwar ba ta kasance ta bayyana ba, kuma ana zargin musabbabin kamar ta'addanci. Furtherarin bincike da irin wannan taron shekaru biyu daga baya a Tafkin Nyos ya haifar da bayanin da aka yarda da shi a halin yanzu. Mutane da yawa sun ba da rahoton jin wata babbar kara a ranar 15 ga Agusta, 1984 da misalin ƙarfe 22:30. An bayar da rahoton cewa wani gajimare mai dauke da iskar gas daga wani rami da ke gabashin tafkin. Mutuwar da aka samu na mazauna a wani yanki mai ƙanƙantar da hankali ana tsammanin ya faru ne tsakanin 03:00 zuwa wayewar gari. An ce wadanda abin ya shafa suna da konewar fata, wanda rahotanni daga baya suka bayyana a matsayin "lalacewar fata" kamar canza launi. Waɗanda suka tsira sun ba da rahoton cewa farin, kamar hayaƙi kamar hayaƙi yana da ƙamshi mai ɗaci da acidic.