The Eastern Mediterranean continental slope offshore Israel became a focus of exploration for, and production of, natural gas in recent years. The 2010–2011 Nautilus ROV expedition performed detailed video recordings and sampling in two areas offshore Israel: the Palmachim disturbance, southwest of Tel Aviv, and an area offshore Acre, north of Haifa. An analytical programme regarding the carbonate structures was carried out, examining the overall mineralogy, stable C and O isotopes, and Ca, Mg, and Mn concentrations. This provided information on their composition and as a result, an indication of the carbon sources and temperature of formation. The major authigenic minerals identified comprised magnesian calcite, dolomite, aragonite, and kutnohorite. The detrital minerals included quartz, clays, feldspars, and rare augite and enstatite, likely transported from the Nile estuary. The carbon isotope composition of aliquots taken from nineteen samples from these areas have an overall δ¹³C range from −62.0 to −0.1‰PDB, indicating a range of microbial/biogenic and thermogenic methane contributions. The range of δ¹⁸O from 2.7 to 7.0‰PDB reflects the range of temperatures of formation. The δ¹⁸O characteristics differ among areas. In general, high values; δ¹⁸O >5‰PDB are recorded from area N2 of the Palmachim disturbance, indicating low temperature of formation. Low values of δ¹⁸O (<5‰PDB) were measured from areas W2 and W3 of the Palmachim disturbance, together with samples from area N2 of the Palmachim disturbance, and samples from areas A1 and A2 offshore Acre indicate high temperature origin. Samples from an inactive chimney from area N2 range from pure dolomite to pure magnesian calcite. This trend is linked to δ¹³C increase from −39.9 to −0.1‰(PDB), and δ¹⁸O decrease from 6.2 to 4.7‰(PDB). These values indicate a decrease in the methane-derived carbon contribution and an increase in temperature. Kutnohorite, Ca(Mn²⁺, Mg, Fe ²⁺)(CO₃)₂ is a major component in samples from Acre, and less so in the Palmachim disturbance. An exploratory investigation of the relationship between Mn/Ca, δ¹⁸O and δ¹³C revealed that samples having Mn/Ca < 0.1(wt./wt.) have δ¹³C<−50‰PDB indicating a microbial methane source, while samples with Mn/Ca > 0.1 have δ¹³C between −35 and −22‰PDB suggesting a thermogenic origin. These results suggest that the mineralogical, isotopic δ¹³, δ¹⁸O, and chemical (Mn/Ca indicative of kutnohorite) characteristics of surficial carbonate structures can indicate and distinguish between deep and shallow methane sources in the Eastern Mediterranean.

以色列近海的东地中海大陆斜坡成为近年来天然气勘探和生产的重点。2010-2011年Nautilus ROV探险队在以色列近海的两个地区进行了详细的录像和采样：特拉维夫西南的Palmachim扰动和海法以北的Acre近海。进行了有关碳酸盐结构的分析程序，检查了总体矿物学，稳定的C和O同位素以及Ca，Mg和Mn的浓度。这提供了有关其成分的信息，结果提供了碳源和地层温度的指示。确定的主要自生矿物包括镁方解石，白云石，文石和库特诺石。碎屑矿物包括石英，粘土，长石以及稀有的辉石和顽辉石，可能是从尼罗河河口运来的。从这些地区的19个样品中提取的等分试样的碳同位素组成总体上具有δ¹³ C的范围为-62.0至-0.1‰PDB，表明微生物/生物源和热源甲烷的贡献范围。δ的范围¹⁸ 2.7〜7.0‰öPDB反映地层的温度的范围内。该δ ¹⁸ O特性方面不同而有差异。一般而言，高价值；δ ¹⁸ O> 5‰PDB从帕尔马奇姆扰动区域N2记录，表明形成的低的温度。δ值低¹⁸O（<5‰PDB）是从Palmachim扰动的W2和W3区域以及Palmachim扰动的N2区域测得的，而Acre和A2海上Acre的样本则表明是高温起因。来自N2区域的惰性烟囱的样品范围从纯白云石到纯镁方解石。这一趋势被链接到δ ¹³ Ç增加从-39.9至-0.1‰（PDB），δ ¹⁸ ö降低6.2至4.7‰（PDB）。这些值表明甲烷衍生的碳贡献降低，温度升高。Kutnohorite，Ca（Mn 2 ⁺，Mg，Fe 2 ⁺）（CO ₃）₂是Acre样品中的主要成分，而在Palmachim干扰中则较少。锰/钙之间的关系的一个试探性调查，δ ¹⁸ O和δ ¹³ C ^揭示有Mn /钙<0.1的是样品（wt./wt。）具有δ ¹³ ç<-50‰PDB指示微生物的甲烷来源，而与锰/钙样品> 0.1具有δ ¹³ -35和-22℃之间‰PDB提示有产热原点。这些结果表明，矿物学，同位素δ ¹³，δ ¹⁸ O，和化学（锰/钙指示kutnohorite的）表层碳酸盐结构的特性可以指示与在地中海深深浅浅的甲烷源之间进行区分。