Stratigraphic Information Research Articles

BUILDING HIGH-PRECISION AMS14C BAYESIAN MODELS FOR THE FORMATION OF PERI-ABANDONMENT DEPOSITS AT BAKING POT, BELIZE

ABSTRACTDeposits linked to abandonment have been widely recorded across the Maya lowlands, associated with the final activities occurring in ceremonial areas of Classic Maya centers. Various models have been applied to explain the activities that lie behind the formation of these contexts, including those linked to rapid abandonment (e.g., warfare) and others focused on more protracted events (termination rituals, and/or pilgrimages). Here, we assess Bayesian models for three chronological scenarios of varying tempo to explain the formation of peri-abandonment deposits at Baking Pot, Belize. Using stratigraphic information from these deposits, hieroglyphic dates recovered on artifacts, and direct dates on human skeletal remains and faunal remains from distinct layers in three deposits in Group B at Baking Pot, we identify multiple depositional events that spanned the eighth to ninth centuries AD. These results suggest that the processes associated with the breakdown of institutionalized rulership and its command of labor to construct and maintain ceremonial spaces were protracted at Baking Pot, with evidence for the final depositional activity dated to the mid-to-late ninth century. This interval of deposition was temporally distinct from the earlier deposition(s) in the eighth century. Together, these data offer a detailed view of the end of the Classic period at Baking Pot, in which the ceremonial spaces of the site slowly fell into disuse over a period of more than a century.

The Oyambre coastal terrace: a detailed sedimentary record of the Last Interglacial Stage in northern Iberia (Cantabrian coast, Spain).

ABSTRACTA detailed study is presented of a 15.3‐m‐thick Pleistocene coastal terrace located on the Cantabrian coast (northern Spain). Stratigraphic, sedimentological, topographic and micropalaeontological information is combined with a chronology based on luminescence dating to characterize the deposits. The sedimentary succession records: (i) a basal transgressive system, consisting of a wave‐cut surface covered by a lower layer of beach gravels and upper beach pebbly sands; and (ii) a thicker upper highstand system (aggrading), comprising medium to very fine aeolian sands interbedded with thin palustrine muds. Luminescence dating involved a detailed sampling strategy (36 samples and two modern analogues) and the use of both quartz optically stimulated luminescence (OSL) and feldspar post‐infrared infrared stimulated luminescence single aliquot regeneration protocols; feldspar results were used to confirm the completeness of bleaching of the quartz OSL signal. The quartz OSL luminescence age–depth relationship shows significant dispersion, but nevertheless two rapid phases of deposition can be clearly identified: one at ~130 ka [Marine Oxygen Isotope Stage (MIS) 5] and one at ~100 ka (MIS 5c). The top of the succession is dated to ~70 ka. The MIS 5e marine maximum flooding surface is identified at an elevation of 6.85 m above mean seal level. This elevation provides evidence of a regional sea‐level highstand for this sector of the Cantabrian coast.

A semi-automatic approach for generating geological profiles by integrating multi-source data

Abstract In early geological data analysis, most geological maps were drawn as raster images by hand or with software, and there were disadvantages such as the inability to edit at any time or change the scale with fidelity. Therefore, the use of modern information technology to perform in-depth processing of geological maps with outdated geological data can meet the purpose of repeated use, analysis, and further knowledge discovery. To address this issue, this study proposes a semi-automatic generation approach for generating geological profiles by integrating multi-source data. This approach utilizes the text content of the stratigraphic information description in the geological report and the corresponding digital elevation model (DEM) data of the study area. It solves the problem of the reuse of outdated data and can reconstruct geological profiles at a low cost in the absence of field measurement data (e.g., drilling data). Finally, we propose two application scenarios, including lithology classification of the stratum and knowledge representation of each stratum object, both of which have sound application effects for further analysis and knowledge discovery. The semi-automatic reconstruction method proposed in this study considers the smooth treatment of geological profiles and topological relations between stratum objects. This method solves the problems of interleaving and morphologic coordination between stratum curves in the past . The result of the vector geological profile can be used for geographic information systems (GIS) functions such as spatial analysis and attribute queries.

Multi-scale DCFF network: a new desert low-frequency noise suppression method

Seismic exploration is an essential way for stratigraphic information acquisition and resource exploitation. However, the unique near surface conditions of the desert region in northwest China pose a special problem. On the one hand, compared with Gaussian noise, desert noise concentrates in the low-frequency band, which is seriously overlapped with those of the effective signals; On the other hand, its nonstationary, nonlinear, and non-Gaussian characteristics seriously affect the accuracy of weak signal recovery and increase the difficulty of noise suppression. In the collected field data, effective signals are often submerged by the intense low-frequency noise. Considering that traditional denoising methods have some limitations on this kind of noise, a new multi-scale dense connection feature fusion (MS-DCFF) denoising convolution neural network is presented in this paper. This denoising network can adaptively learn the potential features of effective signals through multi-scale feature fusion techniques and increase the degree of information exchange by utilizing the dense connections between different blocks. Moreover, we construct relatively complete training dataset containing an effective signal dataset and a noise dataset for desert low-frequency noise suppression, thereby boosting the feasibility of the network for desert noise suppression. Both simulation and field data prove that the superior performance of the proposed MS-DCFF in the aspect of low-frequency noise (mainly includes random noise and surface waves) suppression and effective signal recovery, compared with band-pass filtering, f-x filtering, and DnCNNs.

Mapping long-period soil resonances in the Kathmandu basin using microtremors

This study reports the geostatistical analysis of a set of 40 single-station horizontal-to-vertical spectral ratio (HVSR) passive seismic survey data collected in the Kathmandu basin (Nepal). The Kathmandu basin is characterized by a heterogeneous sedimentary cover and by a complex geo-structural setting, inducing a high spatial variability of the bedrock depth. Due to the complex geological setting, the interpretation and analysis of soil resonance periods derived from the HVSR surveys is challenging, both from the perspective of bedrock depth estimation as well as of seismic-site effects characterization. To exploit the available information, the HVSR data are analyzed by means of a geostatistical approach. First, the spatial continuity structure of HVSR data is investigated and interpreted taking into consideration the geological setting and available stratigraphic and seismic information. Then, the exploitation of potential auxiliary variables, based on surface morphology and distance from outcropping bedrock, is evaluated. Finally, the mapping of HVSR resonance periods, together with the evaluation of interpolation uncertainty, is obtained by means of kriging with external drift interpolation. This work contributes to the characterization of local seismic response of the Kathmandu basin. The resulting map of soil resonance periods is compatible with the results of preceding studies and it is characterized by a high spatial variability, even in areas with a deep bedrock and long resonance periods.

Protracted northward drifting of South China during the assembly of Gondwana: Constraints from the spatial-temporal provenance comparison of Neoproterozoic–Cambrian strata

Abstract Neoproterozoic to Paleozoic sedimentation shows systematic temporal-spatial variations within South China, which must be considered in reconstructing geological evolution of South China in response to global plate reorganization from the breakup of Rodinia to the assembly of Gondwana. We use >1000 new U-Pb and Hf isotopic data for detrital zircons from Neoproterozoic–Cambrian strata across the western (i.e., Longmenshan) and eastern (i.e., Wuyishan) margins of South China, coupled with compiled stratigraphic and magmatic information, to constrain change in provenance through time. First-order conclusions are as follows: (1) detrital zircons from the Neoproterozoic strata of the two margins were mainly sourced from the Panxi-Hannan arc and the Jiangnan orogen, signaling a rough self-sufficient sedimentary system; (2) newly identified Cambrian molasse-like sediments in the western margin, in which abundant detrital zircons are 550–500 Ma old with positive εHf(t) values, were mainly derived from the 580–500 Ma Cadomian arc belt along the Iran-Turkey margin; and (3) the Cambrian sediments in the eastern margin document more increased contributions from the Grenvillian-age provinces most possibly in Australia. Such spatial-temporal provenance variations signal the northward drifting of South China, from a position connecting with Iran-Turkey and northern India to that approaching Australia during the late Neoproterozoic–Cambrian period. We highlight that the activity of oblique oceanic-continental convergence accreted Asian terranes onto the northern margin of Gondwana, hence contributing to the ultimate Gondwana architecture under global plate reorganization.

Building a high‐resolution chronology of a medieval urban site through Bayesian modelling*

This paper shows that combining stratigraphic information with dendrochronological and radiocarbon dating in a Bayesian model is a powerful tool in producing a high‐resolution chronology for a medieval urban site. By using all available archaeological information, it is possible to construct a chronology of higher accuracy, transparency and reproducibility than that created through informal interpretation and ceramics chronologies. The example shows how a modelling process is also a valuable tool in validating and reassessing the stratigraphic interpretations. The model is used on two levels: (1) to establish the overall site chronology; and (2) to investigate the age and duration of individual events and structures. Finally, since the model is constructed independently of ceramics chronologies, it is suggested that the current local ceramics chronology could be revised.

Integration of satellite-based A-DInSAR and geological modeling supporting the prevention from anthropogenic sinkholes: a case study in the urban area of Rome

This paper presents a methodology tuned to support the management of underground pipelines (sewer and aqueduct networks) in Rome, often threatened by the sudden formation of sinkholes related to the upward migration of existing underground cavities. The methodology integrates data coming from the assessment of susceptibility to sinkhole formation and the advanced processing of satellite-based SAR imagery. The former, performed through the multivariate logistic regression technique, relies on a detailed database of stratigraphic and other thematic (i.e. sinkhole inventory and density of underground cavities) information. A-DInSAR processing of satellite images, for which we developed on-purpose algorithms to filter only data relevant for the process under study, allowed us to provide density maps of subsiding reflectors whose likelihood to be precursors of sinkhole collapses is rated based on the integration with the susceptibility map. The procedure is addressed to point out potentially critical ‘hotspots’ that the company managing the underground networks should pay attention to by means of further detailed investigations. Recent (i.e. occurred after the finalization of the products shown in this paper) sinkholes validated the reliability of the procedure adopted, whose strength is the data fusion able to produce refined and focused information starting from independent and more generic datasets.

Catalogue of plant fossils described in works by Kaspar M. Sternberg. Second revised edition

This Catalogue is the second revised and expanded edition of the first edition, published in 1997 by J. Kvaček and Straková. The material presented in the original edition was completely nomenclaturally revised and newly photodocumented. This second edition provides as much updated information as it was possible to acquire. The Catalogue includes and reviews new nomenclatural and taxonomic assignments of Sternberg’s type material and taxa published after 1997. It is clear that much of the impulse to conduct this new research came from the first edition of the Catalogue, as the community realized the type material is available for study. In summary, the second edition of the Catalogue comprises specimens that are types of 82 genera, 3 subgenera, 535 species and 14 varieties described by Kaspar Maria Count Sternberg and his collaborators: K. B. Presl and A. C. J. Corda. The type material of 32 genera, 233 species and 5 varieties is housed in the National Museum, Prague. The types of 79 species and 4 varieties have been located in other European museums. The rest of the type specimens are currently missing – destroyed, lost, or of unknown repository. For available specimens, more detailed taxonomic, stratigraphic and geographical information is provided. All cases are noted where names in Sternberg’s works have priority over names currently used, although the current names may be more widely known. Only two nomenclatural acts are published in the present work; they are designations of a lectotypes for Aspleniopteris difformis Sternb. and Cycadites salicifolius C.Presl in Sternberg.

Automatic Detection of Fractures Based on Optimal Path Search in Well Logging Images

Reservoir fractures are essential locations to gather oil and gas. Recently, imaging logging technology has become a mainstream method for obtaining stratigraphic information. This paper proposed a combined optimal path search strategy to effectively identify and extract the fracture information in well logging images. Specifically, the threshold segmentation of logging images is used to obtain the binary image. In addition, the identification of connected fractures in the logging image is transformed into the optimal path search, and the identification and extraction of reservoir fractures are realized by constructing the optimal path between the two ends of fractures. Finally, an improved ant colony algorithm is applied to filter irrelevant information and extract fractures automatically by recording all the ants’ exploration trajectories in the ant colony. Compared with previous approaches, the proposed method can eliminate irrelevant background features and merely reserve pixels corresponding to fractures. Simultaneously, relative to the conventional strategy, the time consumption is reduced by more than 98%. The findings of this study can help for better extracting fractures automatically and reducing manual workload.

Seismic stratigraphy and the sedimentation history in the Laxmi Basin of the eastern Arabian Sea: Constraints from IODP Expedition 355

Detailed interpretation of seismic stratigraphic sequences in the Laxmi Basin of the eastern Arabian Sea are presented in this study using closely spaced high resolution multi-channel seismic (MCS) data. Our stratigraphic interpretation is further corroborated using recent drilling results in the Laxmi Basin, derived from the long sediment cores collected during International Ocean Discovery Program (IODP) Expedition 355. Integrated core-log interpretation discussed in the present study, offer important insights about the lithostratigraphic variations in this region. Analyses of multi-channel seismic reflection data reveal five depositional sequences (ranging from Paleocene to Recent) that led to the development of this marginal basin since the Cenozoic period. Regional igneous basement is successfully imaged, which was also validated by deep sea coring during the IODP Expedition 355. In the present study, we primarily focus on the post-rift sedimentation in the Laxmi Basin and its possible mechanisms. Our detailed interpretation in the prevailing tectonic framework of the basin suggests that near-shelf oldest volcaniclastic sedimentation immediately overlying the acoustic basement is linked to the onset of India–Madagascar and India–Seychelles rifting activities during the Late Cretaceous period. Eventually, during the Early-Mid to Late Miocene, the basin received maximum sedimentation dominantly through an extensive mass transport mechanism implying possible large-scale deformation on the Indian shelf. Subsequent sediment input to the basin appears to have been fed variably via the Indus Fan as well as coastal discharge from the Indian mainland. The total sediment thickness in the Laxmi Basin ranges from 1.1 to 3.5 km. New stratigraphic information and sediment isopach maps presented here provide vital information about syn- and post-rift sedimentation pattern in the region and their long term tectonic implications.

2D Sequential Restoration and Basin Evolution of the Wichianburi Sub-basin, Phetchabun Basin, Central Thailand

The Wichianburi Sub-basin is currently the only productive area in the southern part of the Phetchabun Basin, central Thailand. It is structurally dominated by NNW-SSE to NNE-SSW trending normal faults as a result of multistage rifting since the Late Oligocene. Half-graben and full-graben basin geometries can be observed from 2D regional seismic sections. In this study, structural restoration techniques were applied to validate the structural interpretation of the original hardcopy of the 2D seismic sections. Stratigraphic information is compiled from published papers and well reports. Our results revealed that most of the deformation was concentrated during the Late Oligocene. Main depocenters for the syn-rift sediments focused in the basin center along the west-dipping normal faults. These faults cut the prerift section and their orientations were possibly controlled by the Permo-Triassic fabrics that underlie the Phetchabun Basin. By measuring the length of the profiles before and after faulting, the restorations show that the extensions of the Wichianburi Subbasin decrease from 12.30% during the main rift phase (Late Oligocene to Early Miocene) to 2.53% during the second phase of rifting. Rifting only focused in the basin center with the development of NNW-SSE to N-S trending intrarift faults. Since the Middle Miocene, the Wichianburi Subbasin has developed under the tectonic phase of post-rift subsidence with interruption by intrusive activities.

Pluridisciplinary evidence for burial for the La Ferrassie 8 Neandertal child

The origin of funerary practices has important implications for the emergence of so-called modern cognitive capacities and behaviour. We provide new multidisciplinary information on the archaeological context of the La Ferrassie 8 Neandertal skeleton (grand abri of La Ferrassie, Dordogne, France), including geochronological data -14C and OSL-, ZooMS and ancient DNA data, geological and stratigraphic information from the surrounding context, complete taphonomic study of the skeleton and associated remains, spatial information from the 1968–1973 excavations, and new (2014) fieldwork data. Our results show that a pit was dug in a sterile sediment layer and the corpse of a two-year-old child was laid there. A hominin bone from this context, identified through Zooarchaeology by Mass Spectrometry (ZooMS) and associated with Neandertal based on its mitochondrial DNA, yielded a direct 14C age of 41.7–40.8 ka cal BP (95%), younger than the 14C dates of the overlying archaeopaleontological layers and the OSL age of the surrounding sediment. This age makes the bone one of the most recent directly dated Neandertals. It is consistent with the age range for the Châtelperronian in the site and in this region and represents the third association of Neandertal taxa to Initial Upper Palaeolithic lithic technocomplex in Western Europe. A detailed multidisciplinary approach, as presented here, is essential to advance understanding of Neandertal behavior, including funerary practices.

Lunar impact crater identification and age estimation with Chang\u2019E data by deep and transfer learning

Impact craters, which can be considered the lunar equivalent of fossils, are the most dominant lunar surface features and record the history of the Solar System. We address the problem of automatic crater detection and age estimation. From initially small numbers of recognized craters and dated craters, i.e., 7895 and 1411, respectively, we progressively identify new craters and estimate their ages with Chang’E data and stratigraphic information by transfer learning using deep neural networks. This results in the identification of 109,956 new craters, which is more than a dozen times greater than the initial number of recognized craters. The formation systems of 18,996 newly detected craters larger than 8 km are estimated. Here, a new lunar crater database for the mid- and low-latitude regions of the Moon is derived and distributed to the planetary community together with the related data analysis.

Understanding the 3D Formation of a Wide Rift: The Central South China Sea Rift System

AbstractRifted margins result from continental lithosphere extension, breakup, and transition to seafloor spreading by modes typically described by end‐member conceptual models. However, current geophysical data challenge these archetypes showing a more complex spectrum of rifting styles. Here, we integrate geophysical and geological observations to constrain the time and space evolution of the central South China Sea (SCS) rift system. We provide new insights into the continental extension mechanisms and continent‐ocean transition (COT) formation from a seismic transect parallel to the extensional direction of the central SCS rift system. We present 850‐km‐wide region of continental crust where distributed extensional deformation formed a pattern of lithospheric boudinage defined by seven 100‐ to 200‐km‐long structural segments. Each segment is formed by an 18‐ to 24‐km‐thick crust sector laterally thinning into an interboudin neck with ≤10‐km ultrathin crust (ß factors ~3.3–6.5). Drill and stratigraphic information support that extension continued at all six interboudin necks in the central SCS until ~23 Ma, when breakup by seafloor spreading propagation reached one of them. We propose that the seven segments evolved as discrete subsystems from early rifting to breakup. Structurally equivalent ultrathin crust grabens occur NE and SW of both SCS conjugate margins, supporting a 3D wide rift mode of deformation across the SCS rift system. The six ultrathin crust contemporaneous necks and the abrupt nature and location of the COT support that the breakup was not controlled by further continental lithospheric thinning but rather was determined by the seafloor spreading propagation toward the SW.

Array and spectral ratio techniques applied to seismic noise to investigate the Campi Flegrei (Italy) subsoil structure at different scales

Abstract. The purpose of this work is to study the subsoil structure of the Campi Flegrei area using both spectral ratios and array techniques applied to seismic noise. We have estimated the dispersion curves of Rayleigh waves by applying the Frequency–Wavenumber (f–k hereinafter) and Modified Spatial Autocorrelation (MSPAC) techniques to the seismic noise recorded by the underground short period seismic Array “ARF”, by the broadband stations of the UNREST experiment and by the broadband stations of the seismic monitoring network of INGV – Osservatorio Vesuviano. We have performed the inversion of a dispersion curve (obtained averaging the f–k and MSPAC dispersion curves of seismic noise and single phase velocity values of coherent transient signals) jointly with the H∕V spectral ratio of the broadband station CELG, to obtain a shear wave velocity model up to 2000 m depth. The best-fit model obtained is in a good agreement with the stratigraphic information available in the area coming from shallow boreholes and deep wells drilled for geothermal exploration. In active volcanic areas, such as Campi Flegrei, the definition of the velocity model is a crucial issue to characterize the physical parameters of the medium. Generally, a high quality characterization of the medium properties helps to separate the contributions of the volcanic source, path and site in the geophysical observables. Therefore, monitoring possible variations in time of such properties in general can help to recognize anomalies due to the volcano dynamics, i.e. fluid migration connected to the volcanic activity.

New geomechanical application utilizing MWD gamma ray logs: An Eagle Ford case study

Understanding mechanical rock properties is essential for optimal well placement and hydraulic stimulation design which directly impacts hydrocarbon productivity from shale reservoirs with ultra-low permeability. Current industrial practice is to assess spatial variability of subsurface mechanical properties through analyzing core and dipole sonic logs. Seismic inversion is another commonly applicable approach. However, although numerous existing approaches have contributed to upstream operators mitigating operational risk, these individual or combined evaluations ultimately require significant cost and time for exploration. These approaches also have limitations identifying fine-scale variability within inter-well spacing or along the length of a horizontal well due to sparse pilot-well control and the intrinsic limitation of seismic resolution. In this study, we propose a new approach to capture spatial variability of Young's modulus utilizing MWD (Measurement While Drilling) gamma ray logs of horizontal wells. The MWD gamma ray log is essentially acquired for the purpose of having geometric and stratigraphic information on well position while drilling in real time. And, due to cost and time related issues, shale operators commonly acquire only MWD log rather than core or wireline log set for horizontal production drilling while the massive pad drilling has the advantage of large areal coverage. Under the circumstance, MWD gamma ray log is often only data having geological implication. In purpose of utilizing MWD gamma ray log for geomechanical approaches, we examined a relationship between gamma ray and Young's modulus acquired from pilot wells. The MWD gamma ray logs were converted into Young's modulus logs and ultimately populated for three-dimensional property modeling. To validate the property model, an integrated assessment using wireline logs, microseismic, and three-dimensional seismic data was conducted. The study results demonstrate that this new geomechanical approach utilizing MWD gamma ray logs can be supportive or even serve as an alternative to the existing approaches. The method enables identification of finer-scale spatial variability than sparse pilot-well control and conventional seismic analysis, which is attributed to the advantage of long-lateral, multi-benched, staggered, and dense production well placement. Based on the reliability and cost-effectiveness of the new approach, we expect it could help upstream operators mitigate risk and uncertainty related to geomechanical properties without excessive spending for exploration and ultimately improve hydrocarbon productivity with optimal well completion strategies.

Study on the Method of Constructing Engineering Geological Three-dimensional Model of Hydrate Area in South China Sea Based on ArcGIS

The trial production of marine natural gas hydrates (NGH) in China is gradually increasing, attracting concerns on related environmental issues. The entire regional conditions of engineering geological environment must be investigated thoroughly before NGH production. These conditions should be defined, among others, in terms of seabed topography, stratigraphic structure, soil types, physical and mechanical characteristics, hazardous geological factors and distributions, and hydrodynamic characteristics, which provide a variety of geological spatial information and can be obtained from different sources. Due to the high cost and low efficiency of deep-sea engineering geological drilling, only few stations can be deployed. Hence, not enough data are available for the construction three-dimensional (3D) geological models. This study considered the data of only a few drilling stations and compared them with well logging and 3D seismic data. First, the engineering geological standard strata were established. Second, we interpreted and exported the stratigraphic (based on virtual boreholes) and spatial information (in terms of X, Y, and Z) of existent geological structures in GeoFrame. Finally, using several technical modules of ArcGIS (i.e., ArcMap, ArcScene, ArcCatalog), we constructed a spatial database and a comprehensively intuitive 3D visualization data management platform for engineering geological environmental surveys and evaluations in the hydrate area. By clicking any element included in the platform, the correspondent data or results can be looked over: this efficient and continuous systematic database can be used to support the future production of NGH in the area.

Qualitative analysis of time series geodata to prevent complications and emergencies during drilling of oil and gas wells

The purpose of the article is a systematic analysis of drilling data obtained from geological and technological measurement stations in real time, taking into account the geological characteristics of the area being drilled for further forecasting the possibility of complications and accidents during drilling and construction of oil and gas wells. Comprehensive analysis showed the lack of basic software for the recognition and prevention of complications and emergencies based on data obtained in real time. An equally important problem is the lack of reliable lithological and stratigraphic information on the description of sludge during geological and technological measurements. The list of geological and geophysical data required to solve the problem of preventing complications and accidents during the drilling of oil and gas wells has been determined. Geological and technological parameters along the wellbore depth obtained in real time were classified according to the degree of their applicability in machine learning methods.

The Matrix: Connecting Time and Space in archaeological stratigraphic records and archives

The records of archaeological stratigraphic data and the relationships between stratigraphic units are fundamental to understanding the overall cohesiveness of the archaeological archive of an excavation. The information about individual units of excavation identified on sites with complex stratigraphy is most often held in the site database records and stratigraphic matrix diagrams, usually documenting relationships based on the laws of stratigraphic superposition and the Harris matrix conventions (Harris 1979). However, once the matrix diagram has been used to record the information during excavation, there is far less consistency in how those stratigraphic records, and any associated phasing information, are finally deposited in the archives. For that valuable data to be successfully identified and re-used (particularly if the rest of the data is in a database), the stratigraphic and phasing data needs to be in a format that can be interrogated as part of the database. In practice, often only a (paper) copy of the matrix diagrams make the archive. This means that the critical temporal and spatio-temporal relationships upon which the phasing of sites is built, cannot usually be interrogated or (re)used without lengthy and wasteful re-keying of that data into another version of the database. The stratigraphic, sequencing and temporal information held in a matrix is fundamental in further studies of the site records and in working out how the site may relate to other excavated sites of similar or related dates and phases. This article will suggest ways in which the stratigraphic data from excavations and the reasoning processes carried out in subsequent analysis could be better managed, to make matrices (re)useable as part of a more integrated digital archive. This article examines how conceptual reference modelling, particularly using temporal relationships, can be used to explore these issues and how associated technologies could enable semantically-enriched deductions about the spatio-temporal and purely temporal relationships that fundamentally link archaeological data together. It will also consider where further work is needed both to deal with analysis of spatial or temporal records and to enhance Bayesian chronological modelling and associated temporal reasoning, and how this may form the basis for new linkages between archaeological information across space-time.