Noemí Aguilera Franco - Academia.edu (original) (raw)

Papers by Noemí Aguilera Franco

A biostratigraphic zonation of the Cenomanian–Coniacian rocks of the Guerrero–Morelos basin (sout... more A biostratigraphic zonation of the Cenomanian–Coniacian rocks of the Guerrero–Morelos basin (southern Mexico) is proposed. The stratigraphic distribution of 70 species of calcareous algae and benthic and planktonic foraminifers is used to characterize four Zones that in ascending order are: Pseudorhapydionina dubia TRZ (Total Range Zone); Whiteinella archaeocretacea IRZ (Interval Range Zone); Helvetoglobotruncana helvetica TRZ, and Marginotruncana sigali IRZ. The top of P. dubia (upper Cenomanian) is marked at the last appearance of the marker fossil, which closely corresponds to the last appearance of most miliolid benthic foraminifers. Over most of the area, the transition from shallow–marine limestones up into pelagic facies occurs within the W. archaeocretacea Zone (uppermost Cenomanian–lowermost Turonian). A characteristic of this zone is the scarcity of both benthic and planktonic foraminifers, including the zonal marker. Most large benthic foraminifers disappear in the lower ...

Oil production from Upper Jurassic reservoirs started in 1977. The most recent oil discoveries ar... more Oil production from Upper Jurassic reservoirs started in 1977. The most recent oil discoveries are the trigger to update the geological model of these plays. Our work integrates different geological analyses and its calibration and correlation around the basin to establish the sequence-stratigraphic, sedimentological, and structural framework. The Kimmeridgian and Lower Tithonian carbonate rocks were deposited in a wide ramp with facies belts oriented SW-NE, from east to west the environments are: tidal flats, lagoon (inner ramp), middle ramp, and outer ramp. From Middle Tithonian onward, the environments are increasingly deep. The most important facies are associated with topographic highs created by salt piercement: oolitic shoals are widely distributed in the middle ramp high energy environments, biogenic shoals are common in the inner ramp lower energy zone, and tempestite accumulations occur in the outer ramp. All of these facies have been affected by diagenetic processes that created secondary porosity, which combined with matrix porosity make them excellent reservoir rocks. Comparing the former play indicators versus the ones obtained by this work, the geological success probability (Pg) improved in 26%; the number of commercial discoveries expected in the play increased 31%; the commercial discoveries average volume grew by almost 100 %; and the prospective resources of the play increased 150 %. These evaluations, combined with many other criteria, will allow us, in the short and medium term, to design the most suitable exploratory strategies.

Revista Mexicana De Ciencias Geologicas, 2003

Se propone una zonificación para el Cenomaniano-Coniaciano en la cuenca de Guerrero-Morelos (sur ... more Se propone una zonificación para el Cenomaniano-Coniaciano en la cuenca de Guerrero-Morelos (sur de México). Con base en la distribución estratigráfica de 70 especies de algas calcáreas, foraminíferos bentónicos y planctónicos, se identificaron cuatro zonas representadas por Pseudorhapydionina dubia (Zona de Rango Total), Whiteinella archaeocretacea (Zona de Intervalo), Helvetoglobotruncana helvetica (Zona de Rango Total) y Marginotruncana sigali (Zona de Intervalo). La cima de Pseudorhapydionina dubia, (Cenomaniano superior), está marcada por la última aparición del fósil índice, la cual coincide con la última aparición de la mayoría de foraminíferos bentónicos (miliólidos). En la mayor parte del área, la transición de calizas marinas someras a las facies pelágicas se presenta dentro de la Zona de W. archaeocretacea (Cenomaniano superior-Turoniano inferior). Una característica de esta zona es la escasez de foraminíferos planctónicos incluyendo el fósil índice. La mayoría de foraminíferos bentónicos desaparece en la parte inferior de esta zona. Los cambios observados dentro de la Zona de W. archaeocretacea refleja los estados sucesivos del ahogamiento de la plataforma. La Zona de H. helvetica (Turoniano inferior-medio) está caracterizada por la primera aparición de H. helvetica y la presencia de dicarinélidos, praeglobotruncánidos, whiteinélidos y hedbergélidos. Esta zona fue identificada en la Formación Mexcala y representa el depósito en condiciones netamente pelágicas. Hacia el este y la parte centro del área de estudio, en facies marinas someras (Formación Cuautla), esta zona está caracterizada por la presencia de hipurítidos quinodermos, algas gimnocodiáceas y udoteáceas y escasos foraminíferos planctónicos. La Zona de Marginotruncana sigali (Turoniano superior-Coniaciano) está caracterizada por la última aparición de H. helvetica, mientras que su cima fue difícil de reconocer. Hacia la parte central y el oriente del área de estudio, esta zona está representada en facies marinas someras abiertas (Formación Cuautla) por un conjunto constituido por hipurítidos (Vaccinites gosaviensis) corales solitarios, algas gymnocodiáceas, calcisferúlidos y escasos foraminíferos planctónicos. El límite Cenomaniano-Turoniano está representado en la parte inferior de la Formación Cuautla. La presencia de moluscos hipurítidos y la diversificación de whiteinélidos pueden usarse para marcar este límite en el área de estudio

Revista Brasileira de Paleontologia, 2019

Plate sections of saccocomid crinoids spotted in the Albian carbonate deposits of the Georgetown ... more Plate sections of saccocomid crinoids spotted in the Albian carbonate deposits of the Georgetown Formation from Sierra Azul (Coahuila, NE, Mexico) are reported and described. These microfossil remains consist of discarded proximal plates and partial thecae, i.e. primibrachial plates and radial pieces of a partial cup. These roveacrinoids are associated with calcisphere blooms and an abundant diversified planktic foraminiferal assemblage, mostly consisting of favusellids. All these features are evidence of a high primary productivity within an unstable deepening environment. Such pelagic crinoids have been so far regarded as opportunistic organisms that thrived during transgressive eustatic levels and phyto-planktic blooms, in abundance/accumulation events all indicative of hypoxic conditions. The overall microfossil assemblage assigns to this finding an Albian-Early Cenomanian age. Such an event might be well correlated and/or contemporaneous to the bundle of hypoxic events known as OAE1. Such saccocomid plates in Albian deposits revive the debate on the transition between the late Jurassic genera (Saccocoma Agassiz and Crassicoma Sieverts-Doreck & Hess, in Hess) and the late Cretaceous ones (mainly Applinocrinus Peck).

Journal of iberian geology: an international publication of earth sciences, 2005

The Cenomanian-Turonian succession of the Guerrero-Morelos basin contains a number of paloecommun... more The Cenomanian-Turonian succession of the Guerrero-Morelos basin contains a number of paloecommunities that can be correlated. These palaeocommunities have been recognized and interpreted as the result of environmental disturbances. Some of these bioevents are probably local (platform-wide) and reflect successive stages of the platform drowning, whereas others have equivalents in other parts of the world and are probably linked to global paleoceanographic changes. Bioevents that can be used for correlation are: 1) the last appearance of Pseudorhapydionina dubia (94.4Ma); 2) the disappearance of most large benthic foraminifers and calcareous algae (94.2Ma); 3) the first appearance of hippuritid mollusks (93.5Ma); 4) the first appearance of Helvetoglobotruncana helvetica (93.0Ma) accompanied by a diversification of keeled planktonic foraminifers. Increase in 13C and TOC values in the deeper-water facies covering the carbonate platform suggests a probable link between the drowning of t...

Revista Mexicana De Ciencias Geologicas, 1995

Graphic correlation shows that the sediment record is incomplete in most sections that embrace th... more Graphic correlation shows that the sediment record is incomplete in most sections that embrace the Cenomanian/ Turonian transition of the Guerrero-Morelos platform. Three Tethyan zones span the Cenomanian/Turonian interval in the Guerrero- Morelos platform. One unconformity is near the base of the Middle-Upper Cenomanian Pseudorhapydionina dubia Zone and several are in the Upper Cenomanian-Lower Turonian Whiteinella archaeocretacea Zone. Continuous deposition resumed at the base of the Lower Turonian Helvetoglobotruncana helvetica Zone. The drowning unconformity of the platform is at the contact between the Morelos and Cuautla or Mexcala formations and is dated as latest Cenomanian. The base of the Turonian at 93.50 Ma is at or a few meters above this disconformable contact in most sections, so drowning began before the end of the Cenomanian by a minimum of 600kyr where the top of the Morelos is not eroded.

Boletín de la Sociedad Geológica Mexicana, 1995

Journal of Iberian Geology, 2004

The Cenomanian-Turonian succession of the Guerrero-Morelos basin contains a number of paloecommun... more The Cenomanian-Turonian succession of the Guerrero-Morelos basin contains a number of paloecommunities that can be correlated. These palaeocommunities have been recognized and interpreted as the result of environmental disturbances. Some of these bioevents are probably local (platform-wide) and reflect successive stages of the platform drowning, whereas others have equivalents in other parts of the world and are probably linked to global paleoceanographic changes. Bioevents that can be used for correlation are: 1) the last appearance of Pseudorhapydionina dubia (94.4Ma); 2) the disappearance of most large benthic foraminifers and calcareous algae (94.2Ma); 3) the first appearance of hippuritid mollusks (93.5Ma); 4) the first appearance of Helvetoglobotruncana helvetica (93.0Ma) accompanied by a diversification of keeled planktonic foraminifers. Increase in 13 C and TOC values in the deeper-water facies covering the carbonate platform suggests a probable link between the drowning of the platform and the global Cenomanian-Turonian Anoxic Event. The deposition of organic-rich facies in the upper Whiteinella archaeocretacea and lower Helvetoglobotruncana helvetica Zones is associated with the establishment of oxygen poor and eutrophic conditions.

EXTENDED ABSTRACT This Lower Tithonian sedimentary interpretation is based on microfacies analysi... more EXTENDED ABSTRACT This Lower Tithonian sedimentary interpretation is based on microfacies analysis of 48 wells. These new features are very important for establishing new paleogeographic configurations and depositional processes as well as new exploratory perspectives in southern Mexico. The calcareous tempestite levels are floatstone and packstone to grainstone of ooids (more rarely wackestone) with peloids and reworked bioclasts (saccocomids, echinoderms, benthic foraminifers, calcareous algae, serpulid fragments, and corals, bryozoans and mollusk fragments, partially dolomitized. These deposits are also very important levels as reservoir rocks; dissolution, fractures and oil impregnation are some of the main important diagenetic features. It is important to mention that these deposits are well represented from the Upper Tithonian to the Kimmeridgian sequences. The presence of these tempestite levels is a fundamental new argument to interpret deposits as characteristic of the deeper parts of a platform or carbonate outer ramp, less than 200 m in depth. The lower Tithonian tem-pestites is a storm deposit, which shows evidence of violent disturbance of pre-existing sediments, followed by their rapid re-deposition in shallow environments. Storms can rework the sediment of the shelf and redeposited it as tempestites in deeper water. The tempestite deposits are characterized by silty limestones showing cross bedding and hummocky structures. They show a massive lower sequence, followed by a secondary level showing parallel laminations, a third level of hummocky structure and finally a fourth level showing ripple marks. The bedding is due to the planar bioclast accommodation and the grain size classification represented mainly by peloids.

Resumen Se describen las facies sedimentarias de la rampa interna del Kimmeridgiano en la Sonda d... more Resumen
Se describen las facies sedimentarias de la rampa interna del Kimmeridgiano en la Sonda de Campeche, interpretadas en muestras de núcleo y de canal de más de 50 pozos. Con base en el análisis sedimentológico detallado, se interpretaron además de los amplios desarrollos de bancos oolíticos, otras facies que se ubican desde la planicie de mareas y la laguna, hasta el borde de rampa interna/rampa externa. Como roca almacén, estas “trampas mixtas” denotan excelente porosidad y permeabilidad y su importancia económica dependerá de su amplitud y distribución.

Cretaceous Research, 1997

Facies successions in three stratigraphic sections (Barranca del Tigre, Axaxacoalco, and Zotoltit... more Facies successions in three stratigraphic sections (Barranca del Tigre, Axaxacoalco, and Zotoltitlán, Guerrero State, southern Mexico) that comprise middle Cenomanian to lower Turonian rocks of the central part of the Guerrero-Morelos Platform, indicate the drowning of some parts of the platform near the Cenomanian-Turonian boundary. In the western part of the study area (Barranca del Tigre section), Cenomanian shallow-marine limestones (mainly subtidal facies) with abundant benthic fauna (mainly foraminifera) pass upwards to a 7-m-interval of Turonian open-marine nodular limestones with few benthic organisms and then to dark-grey and black laminated pelagic limestones and marls. In the west-central part (Axaxacoalco section), Cenomanian restricted shallow-marine limestones (intertidal to subtidal facies) change abruptly upwards to Turonian black and dark-grey laminated pelagic limestones and marls with only pelagic fauna (calcisphaerulids, planktonic foraminifera, and radiolaria). In the eastern part of the study area (Zotoltitlán section), Cenomanian restricted shallow-marine limestones (mainly intertidal facies) are overlain by 45 m of open-marine limestones showing up-section a rapid decrease in benthic diversity until only calcisphaerulids and echinoderm fragments occur. Overlying these rocks, there are 65 m of nodular shaly limestones in thick strata with renewed benthic fauna, 80 m of shaly and silty limestones intercalated with claystones and some siltstones, and finally, dark grey/black laminated pelagic limestones and marls.The facies successions in the stratigraphic sections suggest the progressive drowning of the Guerrero-Morelos Platform around the Cenomanian-Turonian boundary. We attribute the drowning of some parts of the platform to the occurrence of the Cenomanian-Turonian anoxic event. The impingement of anoxic waters over the platform could produce the drastic reduction of the carbonate producing benthos observed in the stratigraphic sections and therefore a reduction in carbonate accumulation rates. Subsidence and the late Cenomanian-earliest Turonian sea-level rise were then able to drown the platform. This occurred first in the western part, where subtidal conditions dominated and an irreversible drowning occurred, allowing the deposition of organic-rich pelagic sediments over pre-existing shallow-marine carbonates. At the same time, the eastern part, where intertidal conditions dominated, changed to open-marine conditions, shallow first and deep later. Here, a temporal restoration of shallow open-marine carbonate sedimentation resulted, but eventually this region was also drowned, probably by the interplay of terrigenous-clastic supply to the platform and a new impingement of anoxic waters.

Zones that in ascending order are: Pseudorhapydionina dubia TRZ (Total Range Zone); Whiteinella a... more Zones that in ascending order are: Pseudorhapydionina dubia TRZ (Total Range Zone); Whiteinella archaeocretacea IRZ (Interval Range Zone); Helvetoglobotruncana helvetica TRZ, and Marginotruncana sigali IRZ. The top of P. dubia (upper Cenomanian) is marked at the last appearance of the marker fossil, which closely corresponds to the last appearance of most miliolid benthic foraminifers. Over most of the area, the transition from shallow-marine limestones up into pelagic facies occurs within the W. archaeocretacea Zone (uppermost Cenomanian-lowermost Turonian). A characteristic of this zone is the scarcity of both benthic and planktonic foraminifers, including the zonal marker. Most large benthic foraminifers disappear in the lower part of this zone. The changes observed within the W. archaeocretacea Zone reflect the successive stages of the platform drowning. The H.

Revista Mexicana De Ciencias Geologicas, 2003

Revista Brasileira de Paleontologia, 2019

Journal of iberian geology: an international publication of earth sciences, 2005

Revista Mexicana De Ciencias Geologicas, 1995

Boletín de la Sociedad Geológica Mexicana, 1995

Journal of Iberian Geology, 2004

The Cenomanian-Turonian succession of the Guerrero-Morelos basin contains a number of paloecommun... more The Cenomanian-Turonian succession of the Guerrero-Morelos basin contains a number of paloecommunities that can be correlated. These palaeocommunities have been recognized and interpreted as the result of environmental disturbances. Some of these bioevents are probably local (platform-wide) and reflect successive stages of the platform drowning, whereas others have equivalents in other parts of the world and are probably linked to global paleoceanographic changes. Bioevents that can be used for correlation are: 1) the last appearance of Pseudorhapydionina dubia (94.4Ma); 2) the disappearance of most large benthic foraminifers and calcareous algae (94.2Ma); 3) the first appearance of hippuritid mollusks (93.5Ma); 4) the first appearance of Helvetoglobotruncana helvetica (93.0Ma) accompanied by a diversification of keeled planktonic foraminifers. Increase in 13 C and TOC values in the deeper-water facies covering the carbonate platform suggests a probable link between the drowning of the platform and the global Cenomanian-Turonian Anoxic Event. The deposition of organic-rich facies in the upper Whiteinella archaeocretacea and lower Helvetoglobotruncana helvetica Zones is associated with the establishment of oxygen poor and eutrophic conditions.

Cretaceous Research, 1997