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Sedimentary Basins - Science topic

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I'm a PhD student researching seismic amplification in a NZ sedimentary basin. I hope that somebody will be able to help me in my interpretation of the 2D seismic lines that traverse the basin. As per the attached image, I am somewhat baffled by the amount confusion in the seismic signals below the surface(shown within red rectangles) that are appearing where I would expect a regular stratigraphic sequence. I have attempted to delineate fault lines but I don't know how successful I am in this aspect. I point out that the mid formation (250-1250m) is consolidated marine sediments, above this mostly sediments from a volcanic source (silts, sands and pebbles mostly unconsolidated).
While the region has historically been understood as passive in terms of seismic activity, this may not be the case as this research may prove.
One of the suggestions for the signal complexity is that the surface region has been so fractured by seismic activity that the resulting unsorted and unstratified volcanic sediments impair the clarity of the signal that is penetrating below.
I hope that someone with experience may have an answer.
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Dave,
Saw your 2D line by chance; nicely complex!
I concur with Jim that post-stack cleaning up of the lines would be helpful. Different interpretation platforms provide different tools. I would recommend filtering in the FK domain. Are the lines migrated?
A comment, the shallow overburden does not contain spark of high reflectivities, supporting an acoustically relatively homogenous interval. Note that you have limited fold at shallow times, i.e. the stack is from a limited number of traces there.
The seismic contains reflective and non-reflective sequences; have an acoustic impedance log and synthetic made of a well if possible. As a rule of thumb, reflective packages relate to sequences with contrasted lithologies, i.e. carbonates interbedded with shales or volcanics with clastics. Transparent units are likely to be more homogenous.
Keep fault geometries simple.
Try to interpret some horizons across the sections and flatten - unflatten the section along those horizons, it may help you figure out what the seismic contains.
Shallow heterogeneities may lead to a cascade of poor imaging, as do fault zones. Imaging of faults on 2D seismic lines running oblique to faults are challenging for fault imaging.
Good luck with your project.
Thomas.
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agglutinated fossil foraminifera buried deeply in sedimentary basins can be used to estimate thermal maturity which is a key factor for petroleum generation , and estimate old marine depths.
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In paleobathymetric studies of Cretaceous-Cenozoic strata, the ratio of planktonic to benthonic species increases with depth from shoreline across continental shelf and slope.
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This is a similar question to a previous posting of mine. I have a range of seismic isochron maps representing different horizons in a sedimentary basin (files attached). I have no further information other than these maps and would like to convert the contours to depth. I point out that the index contours have a depth (in brackets) beside the contour value but I can't work out the intermediate lines. I need to obtain a constant conversion factor and I can't get this from the index values as it changes with increasing TWT.
Also, there a number of parallel lines that bisect the isochrons, are these faults?
Thank you
Dave
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I have sent a similar query to Dave Gardiner in private seven days ago, but he didn't answer until now.
A relevant answer to such a question can only be given if we have more information!
Regards,
Laszlo
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I am developing an inversion algorithm to decipher Moho architecture from observed gravity anomalies using the Airy hypothesis. Therefore, I am in need of a real-world case study to validate my algorithm. I would appreciate it if you could suggest a thick sedimentary basin where I can apply the Airy hypothesis for Moho interpretation.
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You might look at the Anadarko Basin in the US Lower 48. It has 10-12 km of Paleozoic sedimentary cover adjacent to an uplift, The Amarillo-Wichita Uplift, that brings Precambrian rocks to the surface. It has a COCORP seismic study and extensive published interpretation of gravity data by G. Randy Keller and others.
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Are you interested in reservoir characterization? Want to learn about tools that can be applied to oil & gas, critical minerals, and CCUS? Then consider participating in the Premier-Corex short course at the 2023 Rocky Mountain Section AAPG meeting in Bismarck this June. Can't make it to North Dakota? No problem! There's a virtual option. See below for details and links to the meeting registration site:
What: RMS-AAPG Premier Corex Short Course
When: June 4 (Sunday) 2023, 8 am to 5 pm
Where: Radisson Hotel Bismarck (room TBD); virtual component*
Sponsoring Organization(s): Premier-Corex; AAPG Rocky Mountain Section
Title: Applications of Reservoir Characterization Workflows to a Range of Geologic Energy Resources in Sedimentary Basins
Instructors
Mike Dix (Premier Corex) - Geology and petrology
Jules Reed (Premier-Aberdeen) - Core analysis, special core analysis, flow studies in general
Sean Arrington (Premier-Houston) - Rock mechanics
Peter Johnson (Carbon Solutions) - Reactive transport and other modeling
Organizers
Mike Dix (Premier Corex), Bryan Guzman (Premier Corex), Bret Fossum (UND-EERC), Tim Nesheim (NDGS), and Justin Birdwell (USGS)
Description: This 1-day course will provide a review of reservoir characterization workflows for sedimentary basins relevant to development of variety of different resources. A variety of topics will be covered, including (for details, visit: https://www.rms-aapg2023-bismarck.com/short-courses):
Who Should Attend: Geoscientists and engineers interested in reservoir characterization using core, cuttings, and other data types to develop conventional and unconventional oil & gas resources, carbon sequestration prospects, and critical elements/minerals in sedimentary basins.
Morning Schedule
Unconventional Resources (2 hours)
Conventional Resources (2 hours)
Afternoon Schedule
Critical Elements/Minerals (1.5 hours)
CCUS (2.5 hours)
Register here
Fees (in-person and virtual options)
Professionals: $200
Students: $50
Virtual Attendees: $125
*Note, virtual attendees may not be able to view all content due to use of proprietary data in some modules.
Includes: Handouts, presentations, Q&A: light breakfast and boxed lunches provided for in-person attendees
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Is there any effective way to reconstruct the thermal history of deep carbonate formations?
I know that there is a Δ47/(U-Pb) method, but is this method too harsh for the selection of carbonate samples?
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If you have regional knowledge, subsidence history can be restored by using 1D basin modeling (even if is a trusted carbonate sequence). In the process of restoring paleo-heat flow and parameters calibration, you will get the most precise thermal paleoenvironmental formation conditions (regardless of age, e.g. Paleozoic, Cretaceous, Tertiary, etc).
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A good number of Palaeocene-Eocene LBF taxa are reported mostly from the East-Coast sedimentary basins as well as Rajasthan Basins in India. Many of these genera / species have considerable index marker value in the stratigraphy and need to be defined on precise quantitative criteria in order to limit their morphological variation, thus making them more useful for finer stratigraphy. This will also open-up understanding their phylogenetic relationship through geological time. Initially genera like Laffetina, Lockhartia, Sakesaria, Ranikothalia and others may be taken up for the studies.
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I want to believe that the discussion raised seeks to emphasize the need for erecting precise criteria to serve as marker units or stratigraphic horizons based on the abundance of complete absence of certain taxa; and therefore find usefulness in regional correlation schemes. Such criteria should be based on peculiarity of the tools used, if they are fossils markers, are they having the characteristics of guide fossils; if they are geochemical marker, could they be tied to known global geochemical perturbations eg the layer of iridium across the K-T boundary, suggests some control to the hypothesis of the extraterrestrial asteroid impact on the earth that led to the demise of the dinosaurs, etc. I suspect discussions along these lines and their suitability for application is the intent of this discussion raised.
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Hi, my name is Afaha Chidera i'm a 300 level student of Petroleum Engineering, Covenant University. I'm currently working on a presentation, on the Eastern Dahomey Basin, and i've been checking for pictures, detailed images anything that can put a image on how it looks for better explanation in class, all i've been seeing are images on the map showing it's location.
I would really appreciate it if anyone can give me more explanation on it and/or a link for a picture that can help me understand it better. Thank you.
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I am studying the thermal effect of the large Igneous Province recently. Is there any way to do it?
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Dear Xin Liu, China University of Petroleum - Beijing.
I recommend using the magnetic anomalies to estimate the Curie boundary, which indicates, direct or by analogy, the distribution of the thermal anomalies, present-day heat-flow, providing a clear marker for the thermodynamic effect in the crust and mantle. Therefore, I recommend first the use of magnetic anomalies, for example, from the EMAG2 datasets, it is free, and it has the wavelength (deep mantle large-scale structure) that you need in your research.
The knowledge of the magnetic anomalies in LIP (large igneous provinces) regions is a geophysical way, due that the mafic and ultramafic intrusions linked to those LIPs and their contrast in magnetic properties, magnetic susceptibility, using modeling and inversion.
Also, high densities contrast mafic/ultramafic rock compatible with serpentinized, also could show you in gravity anomaly inspection of a LIP, particularly regarding Bouguer complete anomaly map / Residual isostatic anomaly map.
I attached Jennifer Blanchard´s Marter of Science thesis, "Geophysical identification and characterization of mafic-ultramafic intrusions in plume centre regions", 2015, Carleton University, Ottawa, Ontario, Canada. I recommend reading in focus the Modeling methodology, it has wonderful examples.
Best regards, Mario E. Sigismondi
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I found quite huge idiomorphic apatite crystals (up to 0,5 mm) in the Anisian shallow water limestones and they look pretty much like porphyroblasts with pressure shadows. Limestones are highly recrystallized with mylonitic texture.
Whether an increase in temperature can cause the growth of apatites from phosphorus rich limestones?
What is the origin of phosphorus?
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Francolite synonymous with carbonate fluorapatite or
called collophane when microcrystalline
is the principal component of many sedimentary
phosphate rocks (“phosphorite”). Brushite (41.24 wt.% P2O5 ) and
monetite (52.16 wt.% P2O5) are only widespread in guano deposits,
where locally rather exotic phosphate minerals accommodating N, O
and H bridge the gap between organo-mineralic chemical compounds
and inorganic chemical compounds (coastal region in Chile). They can be the source of your apatite when recrystallized.
Marine upwelling along the shelf edge is responsible for the formation of carbonate-hosted phosphates and phosphorites. Some phosphorites accumulated within high energy — nearshore zones. Some formed in the outer shelf deposits. The common minerals besides francolite are smectite, illite, opal, sepiolite, clinoptilolite, quartz , siderite, smectite and palygorskite.
When they undergo physical-chemical alteration, e.g., an increase in T apatite may recrystallize and form XX of different X shape from elongated to stubby XX (pisms). You should investigate your apatite s.s.s. and determine how much carbon dioxide, F , Cl and OH is still in the XX. The OH- and CO3- anion complex should decrease along with increasing T. Also have a look at the minerals associated with the phosphate. The minerals mentioned above only occur in diagenetically overprinted phosphate-bearing limestones.
There are many phosphate deposits hosted by calcareous rocks.
See: DILL, H.G. and KANTOR, W. (1997) Depositional environment, chemical facies and a tentative classification of some selected phosphate accumulations.- Geologisches Jahrbuch, D 105: 3-43.
HGD
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except for the vitrinite reflectance, conodont and acritarch colour alteration, fission tracks, (U-Th)/He, is there any new methods to reconstruct the thermal history of sedimentary basins?
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Carbonate mineralisation can be used to track thermal histories, utilising U-Pb geochronology (giving you time), in combination with clumped isotopes (giving you temperature).
These papers combine these two methods (and there are many others utilising the methods individually):
Mangenot, X., Gasparrini, M., Gerdes, A., Bonifacie, M. and Rouchon, V., 2018. An emerging thermochronometer for carbonate-bearing rocks:∆ 47/(U-Pb). Geology, 46(12), pp.1067-1070.
Pagel, M., Bonifacie, M., Schneider, D.A., Gautheron, C., Brigaud, B., Calmels, D., Cros, A., Saint-Bezar, B., Landrein, P., Sutcliffe, C. and Davis, D., 2018. Improving paleohydrological and diagenetic reconstructions in calcite veins and breccia of a sedimentary basin by combining Δ47 temperature, δ18Owater and U-Pb age. Chemical Geology, 481, pp.1-17.
Brigaud, B., Bonifacie, M., Pagel, M., Blaise, T., Calmels, D., Haurine, F. and Landrein, P., 2020. Past hot fluid flows in limestones detected by Δ47–(U-Pb) and not recorded by other geothermometers. Geology, 48(9), pp.851-856.
MacDonald, J.M., Faithfull, J.W., Roberts, N.M.W., Davies, A.J., Holdsworth, C.M., Newton, M., Williamson, S., Boyce, A. and John, C.M., 2019. Clumped-isotope palaeothermometry and LA-ICP-MS U–Pb dating of lava-pile hydrothermal calcite veins. Contributions to Mineralogy and Petrology, 174(7), pp.1-15.
Looser, N., Madritsch, H., Guillong, M., Laurent, O., Wohlwend, S. and Bernasconi, S.M., 2021. Absolute Age and Temperature Constraints on Deformation Along the Basal Décollement of the Jura Fold‐and‐Thrust Belt From Carbonate U‐Pb Dating and Clumped Isotopes. Tectonics, 40(3), p.e2020TC006439.
Pan, L., Shen, A., Zhao, J.X., Hu, A., Hao, Y., Liang, F., Feng, Y., Wang, X. and Jiang, L., 2020. LA-ICP-MS U-Pb geochronology and clumped isotope constraints on the formation and evolution of an ancient dolomite reservoir: The Middle Permian of northwest Sichuan Basin (SW China). Sedimentary Geology, 407, p.105728.
Hoareau, G., Crognier, N., Lacroix, B., Aubourg, C., Roberts, N.M., Niemi, N., Branellec, M., Beaudoin, N. and Ruiz, I.S., 2021. Combination of Δ47 and U-Pb dating in tectonic calcite veins unravel the last pulses related to the Pyrenean Shortening (Spain). Earth and Planetary Science Letters, 553, p.116636.
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i need to know the different methods and geological parameters for characterization of sedimentary basin and to know the tectonic evolution of that. will it be helpful in getting the mineralization localization.
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I think this book chapter could help you;
Plate Tectonic Evolution of Sedimentary Basins, W.R. Dickinson, January 1978,
That's available on the ResearchGate Server for download.
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Dear colleagues, if someone can answer me, may a Geophysicists who are familiar with both, elastic seismic inversion and effective elastic thickness (EET) estimation from gravity data.
Introduction:
An elastic material such as the Earth´s interior is defined by Vp, Vs, and density.
Density is one of the most important properties influencing the sedimentary basins: Lateral density variations drive mass transport on all scales, from plate tectonics (e.g. Forsyth & Uyeda 1975; Chapple & Tullis 1977; Bunge et al. 2003; Liu & Gurnis 2008; Warners-Ruckstuhl et al. 2012), mantle convection (Turcotte & Schubert 2014) and oil and gas reservoir in sedimentary basins by quantitative seismic, e.g., structure, stratigraphy, velocity, density, porosity (Zhang and McMillan, 2018).
Question:
How is the relationship that may exist between flexural rigidity/density derived from gravity, and elastic parameters derived from seismic prestack elastic inversion? How could constrain the answers?
Best regards, Mario E. Sigismondi
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Topography and gravity are geophysical fields whose joint statistical structure derives from interface-loading processes modulated by the underlying mechanics of isostatic and flexural compensation in the shallow lithosphere. Under this dual statistical-mechanistic viewpoint an estimation problem can be formulated where the knowns are topography and gravity and the principal unknown the elastic flexural rigidity of the lithosphere. In the guise of an equivalent ‘effective elastic thickness’, this important, geographically varying, structural parameter has been the subject of many interpretative studies, but precisely how well it is known or how best it can be found from the data, abundant nonetheless, has remained contentious and unresolved throughout the last few decades of dedicated study. The popular methods whereby admittance or coherence, both spectral measures of the relation between gravity and topography, are inverted for the flexural rigidity, have revealed themselves to have insufficient power to independently constrain both it and the additional unknown initial-loading fraction and load-correlation factors, respectively. Solving this extremely ill-posed inversion problem leads to non-uniqueness and is further complicated by practical considerations such as the choice of regularizing data tapers to render the analysis sufficiently selective both in the spatial and spectral domains. Here, we rewrite the problem in a form amenable to maximum-likelihood estimation theory, which we show yields unbiased, minimum-variance estimates of flexural rigidity, initial-loading fraction and load correlation, each of those separably resolved with little a posteriori correlation between their estimates. We are also able to separately characterize the isotropic spectral shape of the initial-loading processes. Our procedure is well-posed and computationally tractable for the two-interface case. The resulting algorithm is validated by extensive simulations whose behaviour is well matched by an analytical theory with numerous tests for its applicability to real.
.
Best regards,
Neeraj Meena,
Thank you...
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I am looking for an electronic version of:
King, C., Gale, A.S., Barry, T.L. 2016. A revised correlation of Tertiary rocks in the British Isles and adjacent areas of NW Europe. Geological Society of London, London, 724 pp.
I realize that large parts are available via GoogleBooks but many passages are missing there. I am especially interested in the chapters including non-marine deposits, such as those dealing with the North Sea, London and Hampshire basins.
Best regards, Thomas Neubauer
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Yes, you can download it via
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In large sedimentary basins surrounded by mountainous glaciers, mountainous runoff feeding the basin increases as a consequence of enhanced glacier melting. In this context, it woud be useful to assessing this effect if groundwater regime is monitored in regions that are affected, in particular, the alluvial fans.
This qestion intends to stimulate a discussion on this by collecting examples and datasets from different regions to achieve a common understading of the issue.
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What are the strong evidences to distinguish the forearc basin, the intra-arc basin and the back-arc basin in the present sedimentary environment?I would appreciate it if you could explain it in as much detail as possible.
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Dear Mr. Liang:
Fore-arc basins: Contain arc-derived volcaniclastics and material from the subduction complex. Terrigenous input is only close to the continent. The sediments may onlap arc volcanic and deeply eroded plutons.
Back-arc basins: Are representing deep marine environments with volcaniclastic submarine fans interfingering with pelagic muds. Towards the mainland calcareous debris come into being
Intra-arc basins: They contain elements from the bounding arcs with derivation mainly from bimodal volcanics
With kind regards
H.G.Dill
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How spatial inhomogeneity in paleoclimate records biased the interpretation of past climate variability. In some of the model-based studies, the advantage of spatial homogenous gridded data has been discussed beautifully. But I couldn't find any literature or article dealing with the role of the spatial distribution of climate data in paleoclimate study.
I would appreciate your suggestions.
Thank you
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The inhomogeneity of paleoclimate geography was common in deep time. Similar with the Quaternary and present time, inhomogenetic paleoclimate zonations can be interpreted to the results from landform alternation (monsoon, rain shadow), high-pressure zone (Hadley circulation) shifting, and so on. Some cases of the the Cretaceous climate can be found from literatures. Hope it is helpful for your question.
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I am studying a sedimentary basin and there are sediments missed during an uplift episode, I have 3 wells with %Ro values and I want to estimate the amount of the erosion for each well.
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Dear Mr. Ali,
vitrinite reflectance is a subtle tool for metamorphic and diagenetic processes. In the present case the statistical variation is rather high around 0.6 %. How much time to you expect within the hiatuses ? I think that in this case it would have meant to overstress this method. It is not only the thickness which is unknown but also the lithology, texture/structure and the physical parameters such as heat flow, conductivity..... You may get differences for the various hiatuses which you would like to correlate with thickness according to your trend line and in reality it might be due to some of the factors I mentioned above some of which are controlling the Ro values. You must reduce the number of unknowns to one unknown, otherwise you may not obtain reliable results.
I wish you much success
H.G.Dill
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I would like to know the fast and easiest way to differentiate aeolian and fluvial silt by looking at the samples itself.
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- Aeolian silt and sand grains have frosted surfaces due to the the abrasion that they suffered when impacted to each other's.
- Aeolian silt might be better sorted than fluvial silts, while fluvial silts tend to be mixed with fine sand and clays and often have organic matter content.
-In a fluvial system, silts and finer sediments are related to flooding plains, so when the river level grows up and cover the plains around the river, after the energy decreases, the silts, clays and organic matter particles deposit on the flooding plain. Silts also occur in abandoned channels in meandering river systems.
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just wondering if there is any published material on how the stereochemistry of environmentally important biomarkers could be affected by the paleo-strain the rocks in a sedimentary basin were subjected to (e.g. folding).
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Thank you so much. Will check that.
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What is the difference between the hydrogeological system and the aquifer system?
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Well,
hydrogeological system simply means regional hydrogeologic basin including recharge, transition and discharge zone, while aquifer system is a part of the hydrogeologic system. see the attached links.
Regards
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I am looking for publications demonstrating the sedimentation VS subsidence rates in minibasin settings and the controlling factors. Sedimentation type and architecture would be helpful as well.
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See diapir influence on Cambrian reefs in Geological setting of the Moorowie Formation, lower Cambrian ...
and the chapter on the Frome Diapir minibasin (adjacent to Moorowie) in:
Sedimentology, Provenance, and Salt-Sediment Interaction in the Ediacaran Pound Subgroup, Flinders Ranges, South Australia
John Waldon Counts B.Sc., M.Sc.
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Hello every one
I'm looking for finding geochemical-Mineral proxies in order to investigate progradation and transgression Arvand Delta in northwest of Persian Gulf (south-eastern extension of the Mesopotamian sedimentary basin).
I will appreciate you introduce me geochemical - mineralogy proxies (fingerprint) for studying about fall and rise of sea level and better detecting of sedimentary environments (fluvial and tidal, coastal marine).
Also I would appreciate it very much if you introduce another person who has worked on this issue.
Thank you for your kind guidance
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Dear Dr. Rahmati,
The position of kaolinite in stratigraphic successions is a powerful marker or proxy to delineate sequence boundaries, produced by subsequent uplift and subaerial erosions prevailing in non-marine settings in the geologic record.
The XRD structural characteristics of kaolinite, including its crystal growth and perfection, as influenced by kaolin chemical variability for non-marine kaolinitic facies analysis, I hope it is useful in your further research on sedimentological-chemostratigraphic analysis of non-marine (siliciclastic fluvial successions) facies, even for geological correlations. You can find this approach in this paper:
Best Regards,
Mahmoud E. Awad
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Esteemed Geoscientist,
May I request you to kindly provide me an opportunity for joint research work on petroleum geoscience seismic imaging orogenic belt fold and thrust belt sedimentary basin hydrocarbon exploration
IGCP 662 UNESCO PROJECT
IGCP 667 www.ccgm.org
WITH BEST REGARDS
SUNJAY
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Esteemed Academicians,
IGCP 662 UNESCO PROJECT
Orogenic belt fold and thrust belt sedimentary basin hydrocarbon exploration
WITH BEST REGARDS
SUNJAY
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What may be the suitable depth for deep & ultra-deep formation in sedimentary basins?
Deep: > 3500 or 4000 or 4500 m?
Ultra-deep : > 4500 or 5000 or 6000 m?
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Good question.
I worked in oil companies in Brazil at Pre-Sal oil fields. There are a lot wells with more than 6000 m of deep, however the thickness of sea is around of 2000 m. The spot was around 110 °C, thermal isolated by a huge layer of salt.
I agree with ultra deep as 6000 m or more.
Lemos-Santos, D. V.
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Lots of study have suggest that kerogen will be decomposed to generate hydrocarbon and pyrobitum in sedimentary?
Anyhow, what will be the final fate of the kerogen (and pyrobitumen) at extremely high temperatrue (eg. >200℃)?
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Hi Kim,
Thanks a lot for the valuable information. I have read some of the brillent refereences. Do you think that kerogen with high maturity can react to form large amount of CO2 at deeply burial depth with high temperature?
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This facies belong to upper Cretaceous in the Azarbailan, NW Iran. this is a lime sandstone or sandy limestone that deposited in marine environments. I need more discusstons about this facies with references .
Photos take by 4 and 10 lens of microscope.
Tanks
Mobin
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Dear Mr. Nejad,
your attempt to interpret the carbonate (micro) facies is very ambitious and is in my opinion not the correct way because the term facies is a far-reaching one to discuss the origin of a rock unit, in this case a sedimentary one where all available features of different scales need to be considered. The late Professor Walliser from Göttingen University once showed us a hand specimen and said: “ You should not create a new orogeny using only one hand specimen”. With kind regards H.G.Dill
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Hello every one
I'm looking for finding geochemical-Mineral proxies in order to investigate progradation and transgression Arvand Delta in northwest of Persian Gulf (south-eastern extension of the Mesopotamian sedimentary basin).
I will appreciate you introduce me geochemical - mineralogy proxies (fingerprint) for studying about fall and rise of sea level and better detecting of sedimentary environments (fluvial and tidal, coastal marine).
Also I would appreciate it very much if you introduce another person who has worked on this issue.
Thank you for your kind guidance
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Hello Maryam,
Geochemical - mineralogical proxies can be very site specific and depend on the lithology of the watershed. It may be useful to try to distinguish the watershed/fluvial geochemical and/or mineralogical signatures from the coastal/marine ones. If there are other sources of sediments characterized by a different geochemistry, transported to the Arvand delta by longshore transport, or other coastal processes, it is likely the their concentrations will be higher during transgressive phases. Another thing to look into is the dominant grain-size modes between the fluvial and marine sediments. Attached is a paper referring to marine versus fluvial sedimentation in estuarine environment.
Regards,
Mike
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Can anyone suggest me a good numerical modelling software capable of doing a 3D settlement analysis of a sedimentary basin where buildings slump due to self weight consolidation as the study area is formed completely by sedimentary (clay) material brought down by river discharge.
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Dear Vincent,
I suggest you yo take a look at Delft 3D suite. Nowadays it is a free software and works very good in water environments, treating properly sediment transport and deposition and able to be used at rivers, estuaries and ocean.
Good Luck,
Barletta
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Dear Friends: Is there any peer-reviewed research papers/publications regarding influence of oxidation-reduction conditions upon distribution of geochemical elements in coaly sediments? I’ve conducted several downhole ICP-MS analysis followed by systematic well logging operations within a thermal coal mine. Geochemical data processing of the resulted data indicates considerable amounts of trace elements in the coal bearing argillite-shales. I’m now thinking about further studies to answer my doubts regarding the concentration mechanism of the elements and the corresponding mineralization evolution. Hence, the hypothesis is that: Redox condition might effect on the element partitioning process in this sedimentary basin. Any Ideas? Thanks.
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Pleased to meet you!
You're welcome @ Pezhman Rasekh
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To calculate CIA and also plot the data on A-CN-K ternary diagram, I need to know the CaO in silicate minerals only, so reliable correcting method.
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CaO* is the content of CaO incorporated in silicate fraction. McLennan (1993) proposed an indirect method for quantifying CaO content of silicate fraction assuming reasonable values of Ca/Na ratios of silicate material. Procedure for quantification of CaO content (CaO*) of silicate fraction involves subtraction of molar proportion of P2O5 from the molar proportion of total CaO. After subtraction, if the “remaining number of moles” is found to be less than the molar proportion of Na2O, then the “remaining number of moles” is considered as the molar proportion of CaO of silicate fraction. If the “remaining number of moles” is greater than the molar proportion of Na2O, then the molar proportion of Na2O is considered as the molar proportion of CaO of silicate fraction (CaO*).
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I have estimated hydraulic conductivity of aquifer samples in a sedimentary basin from grain size analysis using Hazen, Kozeny -Carman, Brayer,Slitcher,USBR methods and tried to correlate them with the available pumping test data but to my greatest surprise, the correlation coefficient between the Pumping test values and those of the hydraulic conductivity estimated using the above mentioned methods is less than 0.5
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Hello,
When you estimate the hydraulic conductivity from empirical methods, it is important to make sure that the methods apply to our material because grain-size based empirical formulas can be applied only if some validity criteria are respected. Each method has its own criteria. If these criteria are not respected, then there will be a mistake on the assessment of the hydraulic conductivity.
Now, considering the validity criteria are respected for each empirical method, it is usually not surprising to observe a discrepancy between the results of the empirical methods and the results obtained from a pumping test due on the scale effects. Indeed, the empirical methods, based on the grain-size analysis of a unique soil sample, usually underestimate the hydraulic conductivity compared with the hydraulic conductivity calculated from a pumping test. The pumping test tests the aquifer on a larger area than a soil sampling and the pumping test is therefore representative of the hydraulic behavior of a larger volume of aquifer. You should consequently favor pumping test results as the most realistic representativeness of the real aquifer conditions. However, empirical methods based on grain-size analysis are still fine because they are easy to apply and they are very cost effective.
Hope this help and feel free to continue the discussions.
I have also attached in this reply one of my papers which compares the hydraulic conductivity results obtained from grain-size analysis, permeability tests and pumping tests.
All the best
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what means the significance of the presence of ankerite in the anoxic sedimentary environment?
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Dear Mr. Mahboubi Chikh Younes,
ankerite [Ca(Fe++,Mg,Mn)(CO3)2] , an Fe- and Mn-bearing dolomite, is a typical marker mineral like siderite or Fe-bearing calcite, all of which accommodate bivalent iron in their lattice given anoxic conditions exist (may also be present in an oxidizing regime if the pH value allows it). Trivalent iron present under oxidizing conditions cannot enter the structure of these carbonate minerals and occurs, e.g., as “limonite” or hematite along cleavage planes. For a detailed description of the redox condition in an x-y plot displaying the pH and Eh (mV) you need to know the soluble components such as total sulfur or carbon dioxide activities in the aquatic system as well as the temperature of formation. For a detailed information about this issue consult the classical studies of Garrels & Christ 1965, where you will find the basics good for learning.
With kind regards
H.G.Dill
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Hello, every one, I’m a college student. Recently, our group drilled a core in a sedimentary basin, with aim to construct the mountain building and climate change history. Now we obtain the geochemical data, like the major and trace element. However, I don’t know how to differentiate the effect of provenance and climate on the geochemical characters respectively. If we explain the change of element as the climate signals, how can I exclude the effect of the signals of the source rocks and vice versa?
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Dear Mr. Zhang,
your question is comparable to a mathematical equation with several unknowns. With bulk chemical data only this equation cannot be solved. Several times, I have been confronted with an issue like that and my answer is always the same: Follow the classical order of geoscientific investigations: (1) Geology/Paleontology, (2) Mineralogy/Petrography, (3) Geochemistry, (4) Advanced-level studies. Do not put the cart before the horse! Every hint to your question at this level means poking around in the dark and will not help you make progress in your project because the basics are unknown.
Sorry for my blunt way giving you my answer.
With kind regards
H.G.Dill
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the quick transformation zone of clay mineral (especially I/S)usually marks the division of diagenetic stage. it is common or not? How did it come into being?
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Dear professor Towe
you are right
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I am interested in the comparison of historical sedimentation rates as well as mass accumulation rates in sedimentary basins in Quaternary, Pliocene and Miocene. Can anyone supply me with reference? Table would be nice. I suspect that Bengal Fan, Foaz Amazonas, some interior basins are high on the list? I searched but could not find a reference anywhere.
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Dear Nazim,
Metivier and colleagues have published a phenomenal article in 1999 about mass accumulation rates in Asian Basins. You might find it interesting. Here's a link:
And I attach a pdf copy hereby.
Best wishes
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As we know, there are many software for 1D site response analysis, namely SHAKE, DEEPSOIL...
Now, I need a software for 3D site response analysis. Is there any commercial software for 3D analysis of basin response to ground motion?
Can we use ANSYS or ABAQUS or PLAXIS for 3D analysis of basin response to long-period ground motion?
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hy,I would like to know how to enter the parameters of deepsoil to plaxis?
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See photos below
I met these structures on limestone dolomites for the first time ...
They correspond to what types of structures?
How to measure them?
What are the parameters to be taken into account?
What is their importance in the study of sedimentary basins?
Can someone give me PDF documents to understand them better?
Thank you dear colleagues
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The irregular fractures that are filled with (micrite/dolomitic siltstone) looks like a set of fairly early extensional normal faulting in semi-lithified to poorly lithified sediments.  The straighter parallel sets with no fill may have occurred at a later date. I would not be surprised to see some strike-slip motion along the fractures (movement in or out of the picture plane).  You do need thin sections to see what the fracture fill is. 
Good Luck
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Dear all,
The fluvial sediments are highly enriched in Carbonates due to the presence of calcrete nodules (Kankars). It is thereby giving higher percentage of CaO in XRF results which in turn is reducing the concentration of other oxides, especially SiO2% (Attached Excel File). Kindly suggest me best and easiest way to remove the carbonates from sediment powder (oven dried) before doing the XRF analysis. The procedure should not be time consuming since I have huge data.
Looking forward to your kind replies ASAP.
Thanks & regards,
Ashok 
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HCl is by far the easiest method if this acid does not alter other mineral phases such as clay minerals. You can also try to use warm formic, acetic or citric acid I presume.  
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K=0.02, SO4=14.5, Cl=1.5, Na=28
Approximate location of sample: 38°08'21.3"N 46°28'37.4"E
Measurements are accurate and the unite for all the ions is meq/l. 24 water samples are gathered from a river which routes in a sedimentary basin, results are roughly similar for all the samples.
I am not sure about polyhalite but no thenardite reported in the area.
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Some river sections can be either gaining (groundwater discharge) or losing (groundwater recharge, infiltration). The composition of groundwater discharge will vary depending on fluid residence times in the aquifer from recharge to discharge. Recharging groundwater is likely to change composition along the flow line from Ca-Mg HCO3  and Ca-SO4 type fluids (in more arid environments) to NaSO4 type fluids (typical in alluvial aquifers) and then to Na-HCO3 and Na-Cl type fluids. These hydrochemical changes are primarily governed by bacteria, cation exchange, junction potential type reactions that occur as aquifer water changes confinement from unconfined, to semi-confined, and finally confined conditions.  Sulfate at recharge most commonly originates from weathered shales and coals containing pyrite. Sulfate reducing bacteria living in aquifer matrix will gradually consume sulfate along the flow line of in semi-confined aquifers until it is exhausted.  In most basins, sulfate will not be detectable beyond a distance from recharge of a few kilometers or less than 1/2 to 1 km at depth.  So, you may be seeing discharge of water into the river from semi-confined aquifers.  By doing mass balance calculations (using milliequivalents in solution) you should be able to differentiate whether the sulfate discharge is derived from unconfined (Ca-SO4 type fluids) or semi-confined (Na-SO4) type fluids.  Your studies can be supplemented with baseflow analytical methods to help identify zones of discharge.  Here are some useful review articles that will help your understanding.
Sophocleous, M., 2002, Interactions between groundwater and surface water: the state of the science: Hydrogeology Journal, v. 10, p. 52–67, doi: 10.1007/s10040-001-0170-8.
Winter, T.C., 1999, Relation of streams, lakes, and wetlands to groundwater flow systems: Hydrogeology Journal, v. 7, p. 28–45.
Potter, K.W., 2001, A simple method for estimating baseflow at ungaged locations: Journal of the American Water Resources Association, v. 37, p. 177–184, doi: 10.1111/j.1752-1688.2001.tb05484.x.
Smakhtin, V.U., 2001, Low flow hydrology: a review: Journal of Hydrology, v. 240, p. 147–186.
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How to measure and compute the sediment yield in a river basin.
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Measurement:
Sediment load in a river is composed of bed load and suspended load. Central Water Commission (CWC) regularly measures suspended load (gms/litre) at their river gauging sites. Bed load is more difficult to measure and requires the use of bed load samplers.
Computation:
Sediment yield (tons/ha) from a river basin during a given time period can be computed using the Universal Soil Loss Equation and its derivatives.  Inputs required are rainfall, slope, soil type, land use, etc.
The Soil and Water Assessment Tool (SWAT) hydrological model implements this equation and can be conveniently used to map out the spatial distribution of soil loss in the basin.
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Am working on the  birimian Basin granitoids in Ghana. Petrographic observations, major,  trace element and ree geochemistry show that the granitoids rocks have been derived from crustal anatexis of the host proterozoic metasedimentary biotite schist but  isotopic values reported by other authors show that the rocks are from a juvenile mantle source.  However am I of the view that it is the due to the primitive nature of the proterozoic sediments that is given isotopic signatures of a possible mantle source. As such how would like to know how to prove the primitive nature of the host metasedimentary biotite schist in support of my argument using the trace elements and ree. 
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I am also a bit confused - perhaps some more detail as to background and what you are proposing?. WHICH isotopes indicate a primitive origin for the granites and why? What is the chemical and mineralogical composition of the granites? Exactly what origin are you proposing for the granites - pure anatexisis, mixing? Please define what you mean by a primitive nature for the biotite schist - are you referring to its age, or the age of the sediments it was derived from, or the age of the source rocks for the sediments?
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The lacustrine rift basins always are characterized by multiple faults and depositional centers and have undergone multiple tectonic activation episodes. Complex basin architectures of rifted basins are well recorded by the coexistence of multiple faults, uplifts, and and sags (sub-sags).  Besides, the proximal and multiple source sediment provenances create different patterns of multiple cycles, stages and depositional centers with diverse sedimentary facies. Sediment provenance analysis is an important aspect for the non-marine sedimentary basin and is useful for identifying the essential elements of the sedimentary systems. How to provide a clear view of available S2S methods, investigate the sediment provenance and dispersal patterns of the Paleogene may be an important task in the future exploration of the lacustrine rift basins.
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Hello,
The question(s) posed by your are true for almost all sedimentary basins.
What I would recommend is try the following steps:
Subdivide the basin (geographically - in plan view) into sub-basins. This may be based on (a) the geometry and segmentation of the bounding and internal faults (b) geometry and distribution of the provenance domains and (c) a basic understanding / model of the fluvial system that yielded these deposits.
Sample and characterise each of the domains independently (as if they were not linked) in terms of basic sedimentological and paleocurrent data.
Review if they fit into a systematic pattern or not. If not (and I suspect this is more likely), evaluate if the model of the fault systems or the fluvial system needs modifications to explain the deviations... This in iself would provide excellent findings...
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shell is minute with distinctive sculptures, however without a sharp boundary to distinguish the protoconch and teleconch.
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Luoyang:
You may find this link interesting:
Best
Syed
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Based on the sedimentary structures like flaser bedding and intermingling of marine and terrestrial sediments, these traces are probably from tidal flats.
Fellow geologists I appreciate your comments in advance. 
A word file and Also the photos are attached below. 
Regards
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Look as if they might be Ophiomorpha: appears to be a distinct (mud?) lining but in the photos I don't see the distinctive beaded form of the mud lining which is typical of Ohiomorpha. Size and general form are consistent with Opiomorpha.
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These are SEM and sample images of Cretaceous carbonates of Tucano Basin, Brazil.
An approximatelly 5 cm thick layer with high concentration of elongated shapes(coprolites, bioturbation?)  forms a laterally continuous marker in the area, different of stratas bellow and above (microbial mats, ostracodites, etc.).
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 appear to be burrows in a totally homogeneous substrate. I ve only seen this type of bioturbation in mangrove swamps adjacent shallow lagoons in the modern.
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I am working in the Tampico-Misantla Basin in the norteast Mexico wich is a foreland basin that have four tectonosequence boundaries, the first one is related to the rift phases relating that leads to the opening of the Gulf of Mexico (Late Triassic to Late Jurassic-Oxfordian), the second is Passive Margin, but we are found inverted structures during Kimmeridgian and Tithonian, that controlled the sedimentation in the basin. Can you help me to find another analogue?
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Also Dear  Lianqiao Xiong ·and Irving,
It is just not true what Xiong replied. There are reactivated normal faults as thrust faults worldwide. There are papers by Rick Sibson on high fluid pressures allowing steep reverse faults. I work offshore southern California where most of the structure is reactivated normal faults in strike-slip and thrust. I've published on this and also on moderately-dipping strike-slip faults. Similar reactivation occurs also onshore southern and central California. The Gulf of Gonave Haiti is another place, but I only have an abstract. There are papers by Martha Withjack on the rifting process for the north Atlantic with some contractional reactivation. : I think it is offshore Atlantic Canada. I work with Leonardo Seeber on different areas, and he works on Calabria Italy and I recall he mentioned that some or much of the structure is reactivated.
It is unclear in Irving's original question whether he is interested in a change in the tectonics changing the setting from extension to contraction, or if he is asking about just an evolution without a big reorganization.
Again, reactivation is really common in Continental tectonics. Let me know if you want me to post references to my own papers on this subject.
Christopher "Chris" Sorlien
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I am continually getting an error 'ERROR 41423:  Channel is not defined for sediment routing in reach "Reach-1"'. From what I have seen HEC-HMS is not really used for sediment routing but I want to test it out in a simple model (1 sub-basin, 1 outlet connected by a reach). I have set all of parameters according to the User's manual with no luck, has anyone successfully used it? I am using the Uniform Equilibrium sediment method for the reach and the Laursen-Copeland transport potential for the basin. I am unsure how to remedy it. Any suggestions are appreciated. Thank you.
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I've found a temporary solution. The sediment and therefore water quality modelling only work with Kinematic Wave and Muskingum-Cunge routing in HEC-HMS. I believe this is because these are the only two methods that ask for cross-section information. I'm changing the routing methods for my model. Any information on how to do sediment modelling with the Modified Pulse method in HEC-HMS is appreciated!
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Can Origin of Sedimentary Basin be of Non Tectonic type
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You have raised a good question. The answer to that is however rather convoluted.
First be clear what you mean by 'of tectonic origin'. In case you imply that (as some of the respondents have mentioned) a basin which does not have a plate-tectonic origin or linkage; sag basins are perhaps the best class of basins to explain that. But remember that even crustal sag is a result of extension of a larger segment of the crust and is driven by either thermal or isostatic forces; and consequently cannot be delinked from tectonic forces completely. Therefore, in that sense, it will be difficult to find a sedimentary basin of any significant volume, area and thickness to have a non-tectonic origin; except special cases (which I list below).
Before going there, I draw your attention to the work on sedimentary basin classification that emerged after the evolution of the plate tectonic theory. In chronological order, the following works summarise the state of the art on the subject rather too well:
  1. Dickinson, W. R. 1974. Editor: Tectonics and Sedimentation. Society of Economic Paleontologists and Mineralogists Special Publications, 22, 1–27.
  2. Reading, H. G. 1982. Sedimentary basins and global tectonics In: Ballance, H. G. & Reading, H. G. (eds) Sedimentation in Oblique-Slip Mobile Zones. International Association of Sedimentologists Special Publications, 4, 7–26.
  3. Kingston, D. R., Dishroon, C. P. & Williams, P. A. 1983. Hydrocarbon plays and global basin classification. American Association of Petroleum Geologists Bulletin, 67, 2194–2198.
  4. Allen, P. A. & Allen, J. R. 2013. Basin Analysis: Principles and Application to Petroleum Play Assessment, 3rd edn. Wiley-Blackwell, Oxford.
  5. Allen, P.A. and 7 others, 2015. Classification of basins, with special reference to Proterozoic examples. In Mazumder, R. & Eriksson, P. G. (eds) Precambrian Basins of India: Stratigraphic and Tectonic Context. Geological Society, London, Memoirs, 43, 5–28, http://dx.doi.org/10.1144/M43.2
Finally, the truly non-tectonic sedimentary basins are essentially found in
  1. mountainous regions due to withdrawal of ice-caps; that leave behind very large morrains that lead to evolution of intermountain lacustrine basins; and
  2. karstic terrains where large dissolution of carbonates from the bedrocks creates vacuities in the terrain that eventually get filled up with water, leading to sediment deposition.
Most non-tectonic sedimentary basins are essentially a lacustrine basins due the mode of their formation.
Hope this helps.
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Hi,
does anyone know if secondary Love waves can be generated by Rayleigh wave interaction with a sedimentary basin boundary?
I have found prior work that showcases generation of secondary Rayleigh and Love waves due to the incident of S-waves on sedimentary basin boundaries for both the observational case and numerical calculations. From a purely simplified point of view the horizontal energy of a Rayleigh wave should excite Love waves when hitting a perpendicular sedimentary boundary.
Does anyone know of any results pointing towards or against such mechanism.
Any help is greatly appreciated.
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Thanks for the potential references, I will have a look through.
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Hi to all!
I have some difficulties to find this:
Deibis, S., Futyan, A.R.I., Ince, D.M., Morley, R.J., Seymour,
W.P. and Thompson, S., 1986. The stratigraphic framework
of the Nile Delta and its implications with respect to the
regions hydrocarbon potential. Proc. 8th Explor. Conf.,
EGPC Cairo
Can anyone help me?
Thank you! 
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Dear All
I will try yo locate and make a pdf of this paper, but it will take a couple of weeks as I am travelling at the moment. Incidentally, I wrote and presented this paper, not apparent from the author list !!
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It is well-known that AVO utilized the fact that Vp of a rock changes dramatically when 10% of gas saturation is introduced to a full water saturation rock, and it is mainly related to the bulk modulus of the rock which changes dramatically during increasing gas saturation from 0 to 10%. The question is why the decrease in bulk modulus of a rock is not as rapid as it is after 10% of gas saturation. Attached is a general bulk modulus vs water saturation/ gas saturation graph.
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dear Simon,
You can find the detail answer by doing gassmann fluid substitution. You can play around with gas saturation to analysis bulk mod changes.
Here I want to give some analog.
Let say you have value 10 (analogue for 0 gas saturation or water saturated condition)
Then you add value 1 (analogue for let say 10% gas). You can calculate the average: 10+1 devided by 2 equal to 5.5. You can see, the value dramastically drop from 10 to 5.5.
Lets continue, imagine we add gas saturation per 10% or equal to value 1
10 + 1 + 1 devided by 3 equal to 4
10 + 1 + 1 + 1 devided by 4 equal to 3.25
10 + 1 + 1 + 1 + 1 devided by 5 equal to 2.8
So you can see the first gas adding makes original bulk mod drop dramatically to 5.5. Since the gas is adding more the bulk changes drop slighly become 4, then 3.25 then 2.8.
This is simple analogue why adding gas 10% results significant drop compare to 30% or even 80% of gas. It because there is significant different between bulk for quartz in sandstone filled by water compared to sandstone with gas.
I hope I can answer your question
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What is the rationale behind the selection of such grain size?
Can somebody provide any relevant references on the methodology for sampling fine grain active stream sediments?
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Dear Dr. Campos,
your question is closely linked to the scope of your project. Each grain size fraction has its special meaning. I can only speculate on your aim. For chemical analysis, I used to take the grain size interval < 63 µm, for placer and heavy mineral investigation it is wise to take the fraction between 63 and 300 µm. In this case you should know which part of the drainage system you are going to sample. Sometimes, a maximum size of 300 µm can be too low. I realized this when I was looking for cassiterite in the upper reaches of fluvial drainage system. For provenance analysis or stream sediment analysis focusing on target selection it is often also prudent to combine sand-sized material with pebble analysis. I want to make you aware of the geological and geomorphologic setting which both play also a significant part when it comes to constrain the size interval.
I renounce to refer to any paper, because each of the studies behind those publications should have gone through some "brain-storming" with regard to this issue prior to any sampling.
Good luck !
Harald G. Dill
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It is a common experience that from seismic sections one can identify mostly the first order unconformity surfaces and if the data quality is too good, second order events can also be detected. However, when in the same area, well log data is studied, we start getting third order and sometimes still higher order unconformities. I just want to know the practical significance of studying multi-order sequence stratigraphy and ultimately where should we stop.
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I think that a good answer would be: it depends! In large scale exploration, it may be enough if you keep the sequence stratigraphical analysis in the lower frequency packages. But if you are working in a field development, you may need to go to higher frequencies to understand the facies distribution. In many cases, you may also find difficult to define the "end" of the stratigraphic approach (end of external controls as sea level or tectonics). In this case, you will be entering in the world of architectural element (facies associations) and sub-environment of deposition (architectural element association), "packages" that not necessarily have external control. I have a good summary of this question in the attached paper.
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In the study of groundwater circulation in large sedimentry basins, it is neccessary to predict permeability variations with dpth. Different models have been proposed, such as linear and logrithmic ones. However, exceptions are often encountered. Is it now a question if such rule exists for all basins or it is entirely site-specific.
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While it is generally true that both porosity and permeability decreases with depth you can expect abrupt permeability changes with depth.  This is a function of stratigraphy, the composition of sedimentary layers and diagenesis.  Even the same stratigraphic layer, roughly at the same depth may show significant lateral permeability changes due to lateral facies and diagenesis changes.  Sorry, no simple answer.
Regards, Volker
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Dear Experts,
       I am a Master student in Aix-Marseille University, Reservoir Carbonate Geology faculty, France. I am looking further information about the techniques Back-Stripping in sedimentary basins in particular for my higher studies.
Thank you in advanced for your priceless help. 
Yours faithfully, 
SALEM Ramzi. 
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Dear Ramzi,
If you can access the journal, you can find a (rather old) worked example in;
Morton, N. 1987. Jurassic subsidence history in the Hebrides, N.W. Scotland.
Marine and Petroleum Geology vol. 4, pp. 226 -242.
You can also download through Research Gate
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Geothermal waters are contained in formations in large sedimentary basins around the world. However, injection of used water is difficult issue to handle. It is therefore neccessary to improve or enhance the formation PORO by weak acids. CO2 is recommended due to the fact that it helps to reduce emmissions to the atmosphere.
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There is quite some work published on this topic, both, experimentally and numerically. Most the work can be found in Chemical Geology or Journal of Greenhouse Gas Control. If you like I can direct you to some of the papers. The problem is that modeling relies on a well calibrated database for the mineral reactions and some knowledge on mineralogy and petrophysical data such as surface area or porosity. These  properties bear uncertainties that are quite difficult to quantify. The same holds for experiments where many artifacts can impact your geochemical system and I am not sure if this is understood well enough.
I think for what you need carbonic acid might be too weak which means that if, then only carbonates would dissolve and this will still take considerable amounts of time until a significant increase in porosity and therefore permeability is achieved. Acid treatment is usually done using HCl or similar simply because it is a much stronger acid and it would mainly be feasible in carbonate but not in sandstone reservoirs.
I hope this help.
Best wishes, Andreas
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I am working on a project which involves the delineation of  sedimentary basin from a basement terrain. The area of focus is the boundary between the two rock types. I need advise on how best to make use of the aeromagnetic data that covers the entire boundary area
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to add to the submission of Adabanija, also performing ANALYTIC SIGNAL on the residual map would orientate the anomalies along the boundaries to appear directly on their sources.
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''In sedimentary basins, it is commonly assumed that the overburden (sv) is the maximum principle stress and, thus, the least principle stress is oriented horizontally'' (Reilly and Flemings, 2010).
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 I think this article by Zoback et al (2003) may somehow help to answer your question: Determination of stress orientation and magnitude in deep wells
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Hi!
There are many examples of the use of ichnology in hydrocarbon reservoir studies.I'm interested if there are any examles of application of ichnology to theinterpretation of the rocks successions hosting VMS or even other types of metallic deposits (bathymetry,depositional enviroments,relationship of trace fossils development to the sedimentary basins  with volcanic actyvity). I have  one paper of Sainty R.A.(1992)Shallow-Water Stratigraphy at the Mount Chalmers Volcanic-Hosted Massive Sulfide Deposit, Queensland, Australia.  Maybe there is some more recent information?
Thanks
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 Dear Mrs. Berdize,
the ichnofacies has been dealt with and applied in many papers among others in some of mine. For the beginner who is not focussing on these trace fossils in their own rights but wants to use them as a tool for environment analysis like you some textbooks and charts may be helpful. The classical one I have mentioned.
Seilacher, A., 1967  Bathymetry of trace fossils. Marine Geology 5, 413-428.
There are many textbooks on sedimentology like Miall (sand), Selley (general), Porter et al. (shales) which have nice charts to use. For a more detailed interpretation you need to consult an expert.
As you mentioned VMS deposits you can exclude the littoral part and look for trace fossil describing the subtidal part of the marine environment. The latter is only a hint to reduce the number of possibilities.
Best regards
H.G.Dill
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I have discharge data for 10 years. I am trying to find the response of the basin if i had more years data. Please give your valuable suggestions 
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1923
Dear Sir,
If you want to perform flood frequency analysis (by processing annual maximum flow series) using the gumbel distribution/method, then the data length may not be adequate. But you can still perform analysis using 10 data points. Only problem would be regarding the uncertainty in the parameter estimates of the distribution. The uncertainty in the parameter estimation would be more if less data is available. The problem of having inadequate data for frequency analysis can be solved by using either of the alternantives:
1] You can use methods like profile likelihood function or Bayesian approach to account for less amount of data. These methods would try to provide uncertainty associated with the discharge estimates (i.e. quantiles from various return periods).
OR
2] You can use regional frequency analysis to pool data from hydrologically similar sites/gauges and then perform frequency analysis using pooled data.
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Dear all,
      I‘d like to know the sedimentary enviroment of Cratacuous formations, Pre-salt and post-salt formations in  Brazil's Santos basin. If they are  lacustrine environment at riftting period and neritic facies at driftting period? Please show me more informations about the depositional enviroment, especially that of  Itapema and Barra Velha formations.
     Thanks a lot!
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Hi Wang Tong Kui,
The Itapema Formation is interpreted as lacustrine deposits in the final stages of the Rift phase. The proximal facies of this system is represented by alluvial fan conglomerates and sandstones. By the other hand there are still much debate about the sedimentation environment of the Barra Velha Formation (if marine or lacustrine environment). But according to some authors the Barra Velha Formation was deposited in a restricted-lacustrine environment during the Post-Rift phase of the Santos Basin, it means, a transitional environment between continental and shallow marine stages. Such stressful sedimentation environment would have generated ideal conditions to the development of stromatolitic rocks.
I know how hard it must be for you read  scientific papers in portuguese, but I'd like to sugest you the following paper:
Maybe this one can help you in your research.
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sedimentary basin
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Mujtuba:
Harald has nicely pointed out the key issues involved in recognizing sedimentary and tectonic contact. In tectonic thrust contact, the order of superposition may be reversed so that the older rocks overly younger rocks. Very experienced geologists working in Himalayan terrain and elsewhere often failed to recognize this, resulting in faulty age and facies interpretations. 
Best
Syed
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The modern sedimentary pyrite always has light d56Fe composition. The main Fe source of such pyrite should be derived from the terrigenous reactive Fe. The iron compounds involved include Fe oxyhydroxides (ferrihydrite, goethite, lepidocrocite) and Fe oxides (hematite and magnetite). In theory, the Fe oxides involving ferric iron should behave heavy d56Fe. However, study focus on iron isotopic composition of such terrigenous iron oxides is quite limted. Can anyone offer some special cases to prove that such Fe oxides behave heavy d56Fe.
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Nowhere, as far as I know. I was just making some general comments about Fe isotopes in case they would be helpful, and because I couldn't resist
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Gypsum and pyrite are two essential minerals that are being used in the reconstruction of past environmental condition. Several evidence indicated that the authigenic precipitation of gypsum mineral is associated with the evaporation processes. However, authigenic pyrite mineral is linked with the anoxic environment within the lake basin.
My questions are:  
1.       What are the factors affecting the precipitation of gypsum and pyrite minerals?
2.       Is it possible that the gypsum may also precipitate in the fresh water (non-evaporitic) condition?
3.       Is there any evidence that indicates the association of gypsum and pyrite in a freshwater condition?
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Dear Dr. Mishra,
the presence of gypsum and pyrite may simply be predicted by the physical-chemical regime irrespective of the environments of deposition, be it lacustrine or any other freshwater environment.
1. The precipitation of gypsum and pyrite  is controlled by the availability of bivalent Fe and calcium in combination with sulfide or sulfate anions. They precipitate as the solubility product is exceeded.  Pyrite is pecipitated when the Eh is < 0 and gypsum needs an Eh > 0.
2. Yes, if you add, e.g. , Ca(OH)2 to a sulfate-bearing system you will get CaSO4 . 2 H2O;  it does not depend upon the state of evaporation.
3. In many waste dumps at mining sites you can encounter  pyrite being converted into gypsum provided calcium ions are present. The climate needs not be aridic .
You can model it simply by using x-y plots ( x = pH, Y = Eh given in mvolt) with the soluble components being sulfur, iron and calcium in their ionic state.
Best regards
H.G.Dill
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Any specialist on this platform. In sand grade beach sediments, how do you explain the preponderance of rutile over zircon and tuormaline and vice versa while suggesting provenance?
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The predominance of rutile over zircon and tourmaline in beach sand sediments occurs when the area of origin consists of high temperature, high pressure igneous rocks, granites, pegmatites and anorthosites. Furthermore, the rutile came from schists, high pressure gneisses and metamorphosed limestones.
Conversely, tourmaline predominates when tourmaline-rich granites and pegmatites or as well as high-temperature hydrothermal veins are present in the area of origin.
The predominant occurrence of zircons points to areas of origin with mafic pegmatites and carbonatites, as well as zirconium-rich igneous and metamorphic rocks.
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Thin high grade coal deposits including carbonized remains of vegetal matter are known from deep-sea settings of appreciable lateral extent, serving as good source rock for hydrocarbons, such as in South China sea and elsewhere. What specific conditions prevailed in deep-sea to permit genesis of high grade coal? 
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Thin bedded coals are common in deep water sediments in th Kutai Basin, in the Makassar Straits, and offshore Sabah, in sediments mainly of Late Miocene age and form a major hydrocarbon source rock. These have been described by Rui Lin in Indonesian Petroleum Assn (IPA) proceedings and summarised by Saller et al in AAPG Bull.Also described from Sabah. Most organic matter is from angiosperm leaves. These have been illustrated in a paper by myself in IPA in 2011 which discusses the Neogene climate of Makassar Straits.
For such organic rich beds to occur in such abundance in deep marine sediments, you need a major sediment source from an area exhibiting a perhumid lowland equatorial climate, and most importantly this perhumid lowland climate needs to be maintained during periods of sea level lowstand, during which time extensive peat swamps formed around much of the coast of the island of Borneo (most lowstand tropical climates tended to be distinctly seasonal, and hence not peat forming - the Sunda region is the only low latitude area where lowstand peats are known to have widely formed during the Neogene). Coastal instability resulted in downslope transport of leaf-rich sediments in turbidite currents, with the leaf beds settling out typically just after the sands, and sometimes forming beds with a high organic carbon content, and mainly with liptinitic kerogens. Hyperpycnal processes may also be involved  
A confusing aspect of such successions is that due to the high input of organic matter, typical deep marine calcareous microfossils, such as benthonic forams, are missing due to dissolution. Nannofossils and planktonics may also be missing, with only agglutinated forams present. Dating is therefore difficult 
I am very interested to hear of any occurrences of leaf-rich deep marine thin bedded coals from any other areas
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Can we conclude that sedimentation rate in a sedimentary basin increases when chemical weathering at the source area intensifies? (Lacustrine black shale)
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Dear Mr. Moradi,
the critical parameters to give a general answer to your question is the ratio between weathering intensity (physical+chemical) and vertical displacement (uplift in the provenance area + subsidence in the depocenter). If we ignore the physical part of weathering, the parameter which counts is the ratio between uplift/erosion and chemical weathering which depends upon the climatic conditions and in general increases from the pole to the ecquator.
Erosion and weathering are to different processes which work separately from each other.
Your problem has to be discussed from a more geodynamic point of view.
It is the interplay of geology and geomorphology that is reflected in the rate of uplift and weathering. Geodynamic setting, regional geology and geomorphology are closely linked with each other and necessarily have to play hand in hand to concentrate and preserve a zone of chemical weathering . Modern fold belts still on the rise like the Alpine -Central Asian fold belt or the Andes extending along an active plate margin are less likely to provide good conditions for large regolith deposits in the hinterland, even if these geodynamic settings are located in a morphoclimatic zone most suitable for chemical weathering. In contrast, cratonic crustal sections stable over a long period of time with little vertical displacement and passive margin geodynamic settings are preferred crustal sections for thick regolith deposition and preservation. The interaction of vertical displacement and of chemical weathering are decisive for the accumulation and preservation. During slow uplift, chemical weathering operative in the peneplai¬ned hinterland and on the sedimentary bodies in the foreland are instrumental during decomposition of labile constituents from the parent material and their well-balanced interaction enhance the quality and increase the thickness of the residual clay deposits. With increasing rate of uplift, the trend is reversed. Reducing the slope angle or the paleogradient, or in other words moving from the alluvial-colluvial fan system , through the alluvial-fluvial systems into deltaic and swampy rises the likelihood of delineating clay concentration of economic significance like black shales.
As long as your geodynamic setting is not disclosed to the audience I can give you only this general answer.
Best regards
H.G.Dill
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Which method is best to study the subsurface structures in a densely desert basin?
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 Rafik Karaman
Thank you very much.
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