Geological Samples Research Articles

Characterization of ceramic from the Early Bronze Age Xinzhai site, Henan Province, China, by using a multi-analytical approach

This study investigates ceramic production at the Early Bronze Age (ca. 2050–1640 BCE) site of Xinzhai, in central China. The excavation of this settlement produced rich and well-contextualized archaeological material that depicts the Longshan-Erlitou Culture’s development stage. A total of sixty ceramic samples, representative of the various pottery categories and chronological horizons evidenced at this site, and five geological samples gathered around the Xinzhai site were chosen to conduct this analysis. By combining chemical compositional analysis (XRF), spectroscopy analysis (FTIR), and mineral identification (XRD), we were able to define the geochemical signature and mineral characteristics of these ceramics. Ceramic bodies' chemical and mineral composition indicate that raw materials were carefully selected. The firing temperatures of ceramics are between 750 and 950 °C.

A rapid method of simultaneous chromatographic purification of Li and Mg for isotopic analyses using MC-ICP-MS

Lithium (Li) and Magnesium (Mg) isotopes have been widely used as valuable tracers to study geological processes. In general, several column separation procedures have been used to separate Li and Mg. In this study, we present an optimized protocol for the rapid and simultaneous purification of Li and Mg, which significantly reduces the separation time, required reagent volume, and procedural blanks compared to previous methods. Samples with small amounts of Li (generally 5 ng Li yielding Mg masses of 1–1200 μg) were separated, with the corresponding yields of Li and Mg being nearly 100%. Lithium and Mg isotope analyses were performed using an MC-ICP-MS (Thermo Scientific NEPTUNE Plus) and only <0.2 ng Li and <150 ng Mg were consumed for each analysis. Matrix-doping experiments reveal that the matrix effect is negligible for the determination of Li and Mg isotopes from a wide array of geological samples using our protocol. The robustness of the protocol has been validated by replicated analyses of standard solutions and geological standards, which yield long-term external 2σ precision better than ±0.6‰ for δ7Li and ±0.08‰ for δ26Mg. Lithium and Mg isotopic ratios of all reference materials measured in this study agreed well with previous data within uncertainties. The method developed in this study allows for the rapid and high-purity separation of Li and Mg and subsequent high-precision isotopic analyses of these elements.

The Volcanic Landscapes of the Ancient Hunter-Gatherers of the Atacama Desert Through Their Lithic Remains

Since ancient times Andean societies have formed an intimate relationship with volcanoes, the beginnings of which can be traced right back to the initial peopling of the region. By studying rocks used for stone tools and other everyday artifacts, we explore the volcanic landscapes of early hunter-gatherer groups (11,500–9,500 cal BP) of the highlands of the Atacama Desert (22–24°S/67–68°W). Petrological classification of the lithic assemblages of three Early Holocene archaeological sites showed the procurement of a great diversity of volcanic and subvolcanic rocks, including pumice, granitic rocks, micro-diorites, a large variety of tuffs and andesites, dacites, cherts, basalts, obsidians, among others. Field surveys enabled us to detect many of their sources related to volcanic features such as craters, maars, caldera-domes, lava flows, probable hydrothermal deposits, and ignimbrites. In these places, we also document large quarry-workshops and campsites from different periods, indicating intense and repeated human occupation over time. By comparing the artifacts with geological samples collected in the field, it was possible to assign the source of origin of a large part of the archaeological assemblages. Our data suggest that the volcanic features of the Atacama highlands were integrated into the mobility and interaction networks of ancient hunter-gatherer groups at an early date.

Quantitative analysis of the main components in ceramic raw materials based on the desktop LIBS analyzer

The concentrations of SiO2, Al2O3, K2O, Na2O, CaO, MgO, Fe2O3 and TiO2, and loss on ignition (L.O.I.) are the main inorganic components of geological samples. Concentrations of the eight oxides and L.O.I. are also the main indicators of concern in the production of building ceramics. Quantitative analysis of the eight oxides and L.O.I. was performed using fiber-laser-based laser-induced breakdown spectroscopy (LIBS). A combination of continuous background deduction, full width at half maximum (FWHM) intensity integral and spectral sum normalization was proposed for data processing. After the data processing combined the continuous background deduction, FWHM intensity integral and spectral sum normalization, the mean absolute errors (MAEs) of the calibration of L.O.I., SiO2, Al2O3, K2O, Na2O, CaO, MgO, Fe2O3 and TiO2 was reduced from 2.03%, 12.06%, 4.84%, 1.10%, 0.69%, 0.31%, 0.11%, 0.20% and 0.10% to 1.80%, 9.48%, 2.12%, 0.36%, 0.58%, 0.11%, 0.08%, 0.19% and 0.05%, respectively. This multivariate method was further introduced and discussed to improve the analysis performance. The MAEs of L.O.I., SiO2, Al2O3, K2O and Na2O were further reduced to 1.12%, 2.07%, 1.38%, 0.35% and 0.43%, respectively. The results show that the overall prediction error can meet the requirements for the production of building ceramics. The LIBS desktop analyzer has great potential in detection applications on geological samples.

Pressure Effects on Simultaneous Optical and Acoustics Data from Laser-Induced Plasmas in Air: Implications to the Differentiation of Geological Materials.

The shockwave generated alongside the plasma is an intimately linked, yet often neglected additional input for the characterization of solid samples by laser-induced breakdown spectroscopy (LIBS). The present work introduces a dual LIBS-acoustics sensor that takes advantage of the analysis of the acoustic spectrum yielded by shockwaves produced on different geological samples to enhance the discrimination power of LIBS in materials featuring similar optical emission spectra. Six iron-based minerals were tested at a distance of 2 m using 1064 nm laser light and under pressure values ranging from 7 to 1015 mbar. These experimental parameters were selected to assess the effects of pressure, one of the main factors conditioning the propagation of sound as well as a commonly investigated influence in LIBS experiments. Moreover, precise values for carrying out the analyses were set based on one of the most exciting scenarios in which LIBS data may be enhanced by laser-induced acoustics: space exploration. This is exemplified by the tasks performed by the Mars 2020 SuperCam instrument located onboard the Perseverance rover. Authors evaluated the use of acoustic signals both in the time-domain and frequency-domain in sensitive cases for the distinguishing of minerals exhibiting LIBS spectra featuring almost the same emission lines using PCA schemes for each pressure setting. Thus, we report herein the impact of the surrounding pressure level upon this diagnostic tool. Overall, this paper seeks to show how the analytical potential of simultaneous phenomena taking place during a laser-produced plasma event is subjected to the defined operational conditions.

Raman microspectroscopy applied to flint provenance at the chalcolithic settlement of Zambujal (Torres Vedras, Portugal)

AbstractThe mineralogical fingerprint of both archaeological and geological flint, measuring by Raman microspectroscopy the α‐quartz, and the minor elements was studied. Quartz crystallinity index, by XRD, was calculated in geological samples. An estimation of the degree of crystallinity through Raman analysis could be used to infer quartz crystallinity in archaeological materials. The evaluation of moganite content allowed a better differentiation among Cenomanian flints from different places. It was possible to confirm the correlation between archaeological microfacies M1‐TV with the Torres Vedras Cenomanian flint and warn that the M2 flint preliminary associated to Lisboa region could be from another source area.

Advances on microLIBS and microXRF mineralogical and elemental quantitative imaging

Mineralogical and petrographic studies require analytical methods capable to underline the repartition of major to trace elements within geological samples. The EPMA (Electron Probe Micro Analyzer) conventional method used for such investigation, but on restrictive zones, is on the verge to be reached by μLIBS (micro Laser-Induced Breakdown Spectroscopy) and μXRF (micro X-Ray Fluorescence) techniques allowing the elemental imaging on thin rock sections or even larger samples in only several hours. These spectroscopic methods with extremely fast acquisition speed (~10 ms/pixel) are perfectly adapted to perform multi-elemental imaging of major to trace elements down to the ppm-level. Here, on a mica schist thin section that displays a wide paragenesis of minerals, μLIBS and μXRF quantitative elemental mapping are obtained using EPMA spot analyses as internal reference compositions. We exhibit the precision of the μLIBS and μXRF quantitative elemental imaging for major and trace elements repartition in an entire thin/thick rock section. According to these oxide weight contents, a rapid mineral classification is obtained, with a good discrimination between minerals even for those with similar compositions (alumino-silicates such as andalusite and kyanite) and within a complex matrix (Fe-oxides, quartz, micas, feldspars…).

Deep-Sea Seabed Sediment Classification Using Finely Processed Multibeam Backscatter Intensity Data in the Southwest Indian Ridge

In 2007, China discovered a hydrothermal anomaly in the Longqi hydrothermal area of the Southwest Indian Ridge. It was the first seabed hydrothermal area discovered in the ultraslow spreading ocean ridge in the world. Understanding the types of seabed sediments in this area is critical for studying the typical topography and geological characteristics of deep-sea seabed hydrothermal areas. The traditional classification of deep-seabed sediments adopts box sampling or gravity column sampling and identifies the types of seabed sediments through laboratory analysis. However, this classification method has some shortcomings, such as the presence of discrete sampling data points and the failure of full-coverage detection. The geological sampling in deep-sea areas is particularly inefficient. Hence, in this study, the EM122 multibeam sonar data collected in the Longqi hydrothermal area, Southwest Indian Ridge, in April 2019 are used to analyze multibeam backscatter intensity. Considering various errors in the complex deep-sea environment, obtaining backscatter intensity data can truly reflect seabed sediment types. Through unsupervised and supervised classification, the seabed sediment classification in the Longqi hydrothermal area was studied. The results showed that the accuracy of supervised classification is higher than that of unsupervised classification. Thus, unsupervised classification is primarily used for roughly classifying sediment types without on-site geological sampling. Combining the genetic algorithm (GA) and the support vector machine (SVM) neural network, deep-sea sediment types, such as deep-sea clay and calcareous ooze, can be identified rapidly and efficiently. Based on comparative analysis results, the classification accuracy of the GA-SVM neural network is higher than that of the SVM neural network, and it can be effectively applied to the high-precision classification and recognition of deep-sea sediments. In this paper, we demonstrate the fine-scale morphology and surface sediment structure characteristics of the deep-sea seafloor by finely processing high-precision deep-sea multibeam backscatter intensity data. This research can provide accurate seabed topography and sediment data for the exploration of deep-sea hydrothermal resources and the assessment of benthic habitats in deep-sea hydrothermal areas.

Accurate Rock Mineral Characterization With Nuclear Magnetic Resonance

Nuclear magnetic resonance (NMR) logging is a powerful formation evaluation technology that provides mineralogy-independent porosity and helps distinguish clay-bound water, capillary-bound water, and free fluids. NMR logging tool generally operates at 1H NMR frequency of 2 MHz (magnetic field, B0 ~ 470 Gauss) or lower. At this magnetic field, it is only feasible to detect 1H signal from fluids in pores and rely on the relaxation time variation to characterize fluid and pore types. As magnetic field strength increases, NMR sensitivity increases very dramatically, and NMR signals from solid matrix become easier to be detected in high field. For example, NMR at 600 MHz is about 5,000 times more sensitive than the NMR at 2 MHz. Meanwhile, the spectral resolution of high-field NMR is also greatly increased, and high-field NMR spectrum can resolve the detailed differences between molecule types. Therefore, the high sensitivity and spectral resolution of high-field NMR open a totally new horizon for the characterization of geological samples, especially in organic shale reservoirs, in which organic matter and complex mineralogy remain challenging to be accurately characterized. In this work, we report high-field NMR applications for mineral characterization using a 600-MHz NMR spectrometer equipped with a multichannel and Magic-Angle Spinning (MAS) probe. Compared to X-ray diffraction (XRD), which is the primary tool for identifying and quantifying the mineralogy of crystalline compounds in geological samples based on Bragg’s diffraction, NMR can provide more compositional and structural information for noncrystalline compounds due to its sensitivity to local electronic binding structures. Here we demonstrate such an application of high-resolution 27Al NMR to determine the composition and bonding chemistry of 27Al as a fingerprint for a wide range of minerals. The ratio of 27Al at tetrahedral and octahedral binding sites is quantitative and essential to differentiate the dioctahedral and trioctahedral phases. 27Al NMR can also distinguish plagioclase series members ranging from albite to anorthite end members, where Na and Ca atoms can substitute for each other. 27Al NMR can be further combined with 1H, 13C, 29Si, 25Mg, 23Na, and 31P for more detailed mineral determination and clay typing. Our results show that, combined with XRD, this group of high-field NMR spectroscopic methods can greatly improve the accuracy of rock mineral and formation clay characterization in tight-rock and unconventional reservoirs.

Large dynamic range, high resolution optical heterodyne readout for high velocity slip events.

We present a free-space optical displacement sensor for measuring geological slip event displacements within a laboratory setting. This sensor utilizes a fiberized Mach-Zehnder based optical heterodyne system coupled with a digital phase lock loop, providing a large dynamic range (multiple centimeters), high displacement resolution (with an amplitude spectral density of <10-10 m/Hz for frequencies above 100Hz), and high velocity tracking capabilities (up to 4.96m/s). This displacement sensor is used to increase the displacement and the time sensitivity for measuring laboratory-scale earthquakes induced in geological samples by using a triaxial compression apparatus. The sensor architecture provides an improved displacement and time resolution for the millisecond-duration slip events, at high containment and loading pressure and high temperatures. Alternatively, the sensor implementation can be used for other non-contact displacement readouts that required high velocity tracking with low noise and large dynamic range sensing. We use 13 high-velocity slip events in Fontainebleau sandstone to show the large dynamic range displacement tracking ability and displacement amplitude spectral densities to demonstrate the optical readout's unique sensing capabilities.

Mineralogical and Genomic Constraints on the Origin of Microbial Mn Oxide Formation in Complexed Microbial Community at the Terrestrial Hot Spring.

Manganese (Mn) oxides are widespread on the surface environments of the modern Earth. The role of microbial activities in the formation of Mn oxides has been discussed for several decades. However, the mechanisms of microbial Mn oxidation, and its role in complex microbial communities in natural environments, remain uncertain. Here, we report the geochemical, mineralogical, and metagenomic evidence for biogenic Mn oxides, found in Japanese hot spring sinters. The low crystallinity of Mn oxides, and their spatial associations with organic matter, support the biogenic origin of Mn oxides. Specific multicopper oxidases (MCOs), which are considered Mn-oxidizing enzymes, were identified using metagenomic analyses. Nanoscale nuggets of copper sulfides were, also, discovered in the organic matter in Mn-rich sinters. A part of these copper sulfides most likely represents traces of MCOs, and this is the first report of traces of Mn-oxidizing enzyme in geological samples. Metagenomic analyses, surprisingly, indicated a close association of Mn oxides, not only in aerobic but also in anaerobic microbial communities. These new findings offer the unique and unified positions of Mn oxides, with roles that have not been ignored, to sustain anaerobic microbial communities in hot spring environments.

Resin based 3D printing for fabricating reactive porous media

Resin based three-dimensional (3D) printing is popular for many applications including replicating geologic porous media samples. This study is the first to explore resin-based 3D printing of reactive porous media. Here, digital light projection (DLP) 3D printing of sandstone replicates was performed using photosensitive resin mixed with calcite of varying amounts. Printed samples were imaged in 3D using X-ray micro computed tomography (μCT). Printed sample porosities are consistent and close to the original mesh porosity. Calcite volume fractions are generally in agreement with the calcite content in the resin mixture. Calcite accessible surface areas are similar to published values for real sandstones and calcite dissolution was observed in acidic batch experiments, evidence of its surface reactivity. DLP printing is thereby promising for fabricating reactive porous media samples.

Analysis of the Thermogenic Gas Source of Natural Gas Hydrates Over the Dongsha Waters in the Northern South China Sea

Gas hydrates were newly discovered in the Dongsha Waters of the South China Sea by drilling in 2013 and 2019. The drilling results show that the hydrates consist of microbial gas and thermogenic gas, but the source layers of the thermogenic gas are not clear. The Chaoshan depression is the largest relict Mesozoic basin under the Dongsha Waters where thick T3—K strata, up to 5000 m, have developed under thin Cenozoic sediments. The T3—J1 and J3 bear the two main layers of hydrocarbon source rocks rich in II2-III type organic matter, mainly in the western sag, the middle low bulge, and the eastern sag. The T3—J1 developed bathyal - neritic mud rocks, generally greater than 400 m in thickness. The J3 mainly developed closed and semi-closed bay type mud, also II2-III type. Nowadays these two layers are in their mature - over mature stages, thus potentially high-producing. There have developed deep faults cutting through the Mesozoic strata and distributing fractures within the Cenozoic sediments. Analysis of geochemical and geological samples dredged from the seabed indicates a significant oil and gas leakage activity well correlated spatially with the Mesozoic-associated faults. The association of fault-fractures can act as good channels for the thermogenic gas to move upward and diffuse into the temperature pressure stabilization zone of the hydrate. Thus, sufficient gas from the Mesozoic production layers is deemed the main source of thermogenic gas. The area where the Mesozoic faults are activated is the main leakage area of thermogenic gas, thus the main target for future hydrate exploration.

Determination of Fe and Tb concentrations in geological and environmental samples using the instrumental neutron activation analysis method combined with the γ − γ coincidence technique

The instrumental neutron activation analysis (INAA) method was combined with the γ − γ coincidence technique to measure Iron (Fe) and Terbium (Tb) concentrations in geological (Montana II Soil) and environmental (Coal Fly Ash) standard materials. The measured concentrations, which agree well with the corresponding certified values, are compared with those obtained from the traditional INAA method. It is demonstrated that employing the γ − γ coincidence technique slightly improves the accuracy of the analysis. Furthermore, the coincidence technique enhances the detection limits of Tb by ∼4.5 and ∼5.5 times in environmental and geological samples, respectively, but has almost no enhancement in those of Fe. The γ − γ coincidence technique therefore does not always promote the analysis quality of the INAA method, but it is effective for analyzing elements whose characteristic γ rays sustain a high Compton background and/or are overlapped with other γ rays.

Spectroscopic autoradiography of alpha particles using a parallel ionization multiplier gaseous detector

Geoscience is a field of study where nuclear instruments find their place for conducting specific measurements of radioactivity, usually to improve the monitoring of natural processes using naturally-occurring radioactive tracers, but also for the nuclear industry linked to the mining sector. In geological samples, the location and identification of the minerals bearing radioactivity at the thin-section scale remains a major challenge as the detection limit of the usual elementary microprobe techniques is far higher than the concentration of most of the natural radioactive decay products. The location of each decay product, as in the case of uranium-238 series in a geomaterial is interesting for relating radionuclide concentrations to mineralogy. The present study aims to provide spectroscopic autoradiography analysis method for measuring the initial energy of alpha particles with a parallel ionization multiplier gaseous detector. This spectroscopic autoradiography method was successfully used to reproduce the alpha spectra from a 238U decay chain on a geological sample at the thin-section scale. The characteristics of this measurement are an energy spectrum resolution of 17.2% (FWHM) at 4647 keV and a spatial resolution of at least 50 μm. Even if the efficiency of energy spectrum reconstruction is low (4.4%) compared to the efficiency of a simple autoradiograph (50%), this novel measurement approach offers the opportunity to select areas on an autoradiograph to perform an energy spectrum analysis within that area. This opens up possibilities for the detailed analysis of heterogeneous geological samples containing natural alpha emitters such as uranium-238 and radium-226.

Equivalent dose estimation of calcite using isothermal thermoluminescence signals

Thermoluminescence (TL) signals of calcite can be used to potentially date geological and archaeological events back to several million years. However, several issues, such as spurious TL signals appearing at temperatures above 300 °C, have hindered its application to a wide range of samples. A single-aliquot regenerative-dose (SAR) protocol for calcite with low-temperature measurements is proposed to measure the equivalent dose (D e ). It uses the isothermal TL (ITL) signals measured at around 225-240 °C, where a D e vs. ITL temperature (D e -T) plateau can be observed. The width of the temperature range of such a plateau can be sample dependent, as it relates to the proportional contributions of the signals from corresponding TL peaks. The signal at the ITL temperature plateau range largely corresponds to the TL signals of the 280 °C TL peak. D e values obtained by the SAR-ITL protocol are in agreement with those of the multiple-aliquot additive-dose (MAA)-TL and MAA-ITL protocols. The absence of detectable anomalous fading of ITL signals at 235 °C in this and previous studies indicates that the signal is free of fading. Dose recovery tests confirm the suitability of the SAR-ITL protocol for D e estimation. The SAR-ITL protocol measured with temperatures below 300 °C avoids the effects of spurious luminescence signals induced by high-temperature heating. The dose-response curves for ITL signals at 230-235 °C have large characteristic saturation doses (D 0 ) of ∼2000-2400 Gy. The SAR-ITL protocol for calcite thus has the potential to date geological and archaeological samples spanning the entire Quaternary period. • Thermoluminescence (TL) and isothermal TL properties of calcite are investigated. • Equivalent dose plateau using isothermal TL signals is identified within ∼225-240 °C. • SAR-ITL protocol avoids the influence of spurious signals appearing at >300 °C. • Isothermal TL signals of calcite at ∼230-235 °C saturate at ∼4800 Gy.

Standardization procedure to provide a unified multi-method elemental compositional dataset, application to ferruginous colouring matters from Namibia

Curation of archaeological materials often leads to carrying out multi-analytical methodologies that combine non-invasive and invasive elemental analyses. Such materials are often analysed with different techniques. It results in the production of complementary but apparently non-compatible compositional datasets that cannot be easily compared. In the present paper, we propose to compare results acquired on geological ferruginous colouring matters from Namibia with analytical techniques (X-Ray Fluorescence spectrometry (XRF), Proton-Induced-X-ray Emission spectrometry (PIXE), Inductively Coupled Plasma coupled to Optical Emission spectrometry (ICP-OES) and Inductively Coupled Plasma coupled to Mass Spectrometry (ICP-MS)). We aim to provide a unified elemental dataset about these ferruginous colouring matters, usually referred to as “ochre” in archaeology. Analysed geological samples come from three distinct tectonostratigraphic zones of Namibia surveyed in the frame of rock art research. When compared directly, three of the four datasets obtained from these measurements appear as non-compatible because of the inter-equipment variability. However, through a simple standardization procedure, we demonstrate that it is possible to unify these datasets. This procedure minimizes the inter-equipment variability, making the inter-zones of provenance predominant and allowing distinctions of the samples according to their sole origin. Beyond shedding new light on the possibility to compare different elemental analytical techniques, this procedure paves the way for complementary multimodal studies of ferruginous colouring matters.

A comparative performance of machine learning algorithms on laser‐induced breakdown spectroscopy data of minerals

AbstractThe exploration and analyses of chemical components in (extra‐)terrestrial geological materials (such as asteroids and meteorites) are insightful in modern research. Laser‐induced breakdown spectroscopy (LiBS) is a popular method for analyzing the chemical attributes of geologic samples—which scientists use to study and understand planetary bodies and their complex histories. In the literature, several machine learning models that produce high‐accuracy predictions have been proposed. In our work, we compared the performances of such models in predicting elemental abundances on a certain spectroscopic dataset. Models included partial least squares (PLS), extreme gradient boost machines (XGB), neural networks, and linear models. In our results, we showed how PLS and XGB are superior in terms of high predictive power, their ability to generalize, and their reasonably efficient runtimes. In addition, we proposed Ensemble models that aggregate predictions of top‐tier models and observed that they can be desirable. We intend to gain better understanding of how these models perform in predicting elemental compositions on specific spectrum (LIBS) datasets.

Exploring planet geology through force-feedback telemanipulation from orbit.

Current space exploration roadmaps envision exploring the surface geology of celestial bodies with robots for both scientific research and in situ resource utilization. In such unstructured, poorly lit, complex, and remote environments, automation is not always possible, and some tasks, such as geological sampling, require direct teleoperation aided by force-feedback (FF). The operator would be on an orbiting spacecraft, and poor bandwidth, high latency, and packet loss from orbit to ground mean that safe, stable, and transparent interaction is a substantial technical challenge. For this scenario, a control method was developed that ensures stability at high delay without reduction in speed or loss of positioning accuracy. At the same time, a new level of safety is achieved not only through FF itself but also through an intrinsic property of the approach preventing hard impacts. On the basis of this method, a tele-exploration scenario was simulated in the Analog-1 experiment with an astronaut on the International Space Station (ISS) using a 6-degree-of-freedom (DoF) FF capable haptic input device to control a mobile robot with manipulator on Earth to collect rock samples. The 6-DoF FF telemanipulation from space was performed at a round-trip communication delay constantly between 770 and 850 milliseconds and an average packet loss of 1.27%. This experiment showcases the feasibility of a complete space exploration scenario via haptic telemanipulation under spaceflight conditions. The results underline the benefits of this control method for safe and accurate interactions and of haptic feedback in general.

Nano‐FTIR Investigation of the CM Chondrite Allan Hills 83100

AbstractMid‐infrared (MIR) spectroscopy has been used with great success to quantitatively determine the mineralogy of geologic samples. It has been employed in a variety of contexts from determining bulk composition of powdered samples to spectroscopic imaging of rock thin sections via micro‐Fourier transform infrared (micro‐FTIR) imaging spectroscopy. Recent advances allow for IR measurements at the nanoscale. Near field nanoscale infrared imaging and spectroscopy with a broadband source (nano‐FTIR) enable understanding of the spatial relationships between compositionally distinct materials within a sample. This will be of particular use when analyzing returned samples from Bennu and Ryugu, which are thought to be compositionally like CI or CM1/2 carbonaceous chondrites. Returned samples will likely contain olivine/pyroxene chondrules that have been transformed into hydrous phyllosilicates, sulfides, carbonates, and other alteration phases. The use of near‐field infrared techniques to probe the boundaries between once pristine chondrules and alteration phases at the nanoscale is a novel approach to furthering our understanding of the compositional evolution of carbonaceous asteroids and the processes that drive their evolution. Here we report the results of nano‐FTIR spectroscopy and imaging measurements performed on the carbonaceous chondrite Allan Hills (ALH) 83100 (CM1/2). We show with nanoscale resolution that spatially resolved Fe‐Mg variations exist within the phyllosilicates around a chondrule rim. We also present effects of crystal orientation on the nano‐FTIR spectra to account for the spectral differences between the meteorite and mineral spectra.