科学家在嵌入新西兰北部海边悬崖中的一个5米宽的碳酸盐矿物团中发现了许多带壳微生物的化石（如上图），而这些微生物只有在海底渗漏碳氢化合物——例如甲烷或天然沥青——的地方才能够茁壮成长。

尽管这个矿物团如今位于海平面上方几米的地方，但是分析表明，在2000万年前，这些矿物质形成于海平面下600米到2000米的区域中，而甲烷正是从海底的这些地方渗漏出来的。大多数的生物都栖息在这样的渗漏环境中，包括一些微生物也生活在附近的水域中。

而此次在碳酸盐矿物中发现的Amphimorphinella butonensis是一种已经灭绝且极为罕见的物种，之前仅发现于印度尼西亚中部的石灰岩中。在深海碳氢化合物渗漏遗址中再次发现Amphimorphinella butonensis，表明生物能够适应一些独一无二的环境。研究人员在5月的《地质学》杂志网络版上报告了这一发现。

原文出处：

GEOLOGY  doi: 10.1130/G31974.1

An extinct foraminifer endemic to hydrocarbon seeps

Bruce W. Hayward1, Murray R. Gregory2 and James P. Kennett3

Modern seafloor hydrocarbon seeps are usually surrounded by an unusual macrobiota dominated by symbiont-bearing endemic bivalves and worms. Numerous species of foraminifera (shelled protists) also live around hydrocarbon seeps, but none have been found that are endemic to this environment. An extinct species of benthic foraminifera (Amphimorphinella butonensis) has been found in large numbers in a 15-m-diameter patch of siltstone surrounding a Miocene concretionary carbonate mound (inferred to be a fossil methane seep) in New Zealand. The tests exhibit highly negative δ13C values, consistent with a methane-rich environment of recrystallization on or just below the seafloor. This extremely rare species has been recorded only once before, from asphalt-impregnated Miocene muddy limestone in Indonesia, most likely also associated with hydrocarbon seepage. Is this the first record of a foraminiferal species that was specifically adapted, and endemic, to hydrocarbon seep environments?