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Chicxulub, Yucatan, Mexico

Chicxulub Scientific Core Drilling Services Project

 

Chicxulub

 

During April and May 2016, DOSECC participated as part of a joint IODP-ICDP Mission Specific Platform on Expedition 364 on the L/B Myrtle in the Chicxulub Crater as part of the European Consortium for Ocean Research Drilling.  The team was tasked with drilling to 1,500 m below the bottom of the ocean to obtain the first offshore core samples from the peak ring in the central zone of the crater.  

The Chicxulub Crater is an impact crater straddling land and sea on the Mexican Yucatán Peninsula.  The estimated date of the impact which created the crater is now widely accepted as the event that triggered the mass extinction of over 70% of life on earth during the the Cretaceous–Paleogene boundary (K–Pg boundary), approximately 66 million years ago, including the global extinction of non-avian dinosaurs.

The crater itself is believed to have been created by an asteroid with an estimated diameter of 60 km, leaving a crater over 180 km in diameter and 20 km deep. After its discovery in the 1970s, it was confirmed in 1991 as an impact crater due to the discovery of shocked quartz, a gravity anomaly, and tektites in surrounding areas, including samples high in iridium. The minerals around the crater layer include limestone and marl to a depth of almost 1,000 m (3,300 ft) and date to the Paleocene era.  Underneath this layer, another 500 m of andesite glass and breccia are found.  However, within the crater, these andesitic igneous rocks were only found as shocked quartz and the K–Pg boundary is depressed to 600 to 1,100 m (average depth is about 500 m surrounding the crater).

The Chicxulub Crater is the only known crater on the planet with a remaining impact peak ring.  However, the ring is located under 600 m of sediment.  This project revealed the peak ring to be a thick layer of broken, melted rock just beneath a layer of sandstone, which may point to the possibility of an enormous tsunami triggered by the impact.

Upon the successful completion of the project, the samples were shipped to Bremen, Germany, where ECORD Science Party members will then analyze the samples to determine the formation of the peak ring and to calculate total impact energy. Samples taken reflect the post-impact conditions from the Eocene era, between 50 and 55 million years ago, and will likely reveal through the sediment and fossil record new information about how the environment and life began to recover after the cataclysm.

Read related blog posts:

Preparing for Chicxulub: Time Lapse of the Load

A Birds-Eye View of the Rig at Chicxulub, DOSECC Core Drilling Services

Chicxulub Project Watched Around the World

Chicxulub Project Report from the Yucatan

DOSECC Recognized by ESO Expedition 364 at the Chicxulub Impact Crater

DOSECC Chicxulub Project Covered on MSN

NPR Coverage of DOSECC Drilling Project in Chicxulub

Shattered Earth Making Rock Flow – ESO Expedition 364

BBC Coverage on how cores from this project are being studied

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Chicxulub Project Report from the Yucatan

Chicxulub Project Report

English Translation of Yucatan Article


This month Mission 364 began research work at the Chicxulub Crater site. Scientists in charge of the project are encouraging and say they already are seeing interesting results.

The evidence found in the layers of earth found 32 kilometers from the sea port of Progreso confirms the prehistoric stage of the event.  To successfully complete the project, the team had to reach the layer of the meteorite impact under the Gulf of Mexico.  Experts expect to obtain samples of microbial life that reveal data on the recovery of life after the crash of the celestial body which is believed to have caused the extinction of 76% of life in the Cretaceous period.

 

So far the project has resulted in 100 cores of sediment and rock fragments with an approximate age of 66 million years, which corroborate the geological timeframe of the phenomenon being studied.  The evidence being collected will allow researchers, after an exhaustive analysis in German laboratories, to determine whether or not microorganisms were able to survive in the area covered by the impact area.

 

Background


In 1952, Pemex began drilling the first well in the subsoil called “Chicxulub 1”. That drilling confirmed that there was no oil in that region of Yucatan, but some anomalies were discovered in the lower strata. Geophysical studies later determined the existence of a crater in the area.

Decades later and after further studies, on Saturday [May] 14, a team of researchers tackled the Myrtle drilling platform to begin drilling in the earth’s crust in the area of ​​impact.  The first rock samples were found at a depth of 500 meters, the final goal is 1,500 meters.

To understand the work being done on the platform, reporters from Grupa Megamedia set sail aboard the ship “Linda F.” and came to the place called Chicxulub Crater. There, a group of scientists led by Drs. Jaime Urrutia Fucugauchi and Ligia Pérez-Cruz, the Institute of Geophysics of the UNAM and other specialists from six countries explained the progress of the investigation, how they obtained the samples, and how the core analysis will be studied to confirm their theories.

“The expectations we had at the beginning of the project are being met, as we have drilled almost 750 meters and the first part corresponding to the stage of Paleogene, where some microfossils were found, which could imply the analysis was done in the preliminary strata,” explains Dr.. Ligia Perez-Cruz.

 

After a brief tour on the platform to better understand the laboratories and the methods used to extract samples, Dr. Sean Gulick of the Institute of Geophysics at the University of Texas, and Dr. Joanna Morgan of Imperial College in London, said that after drilling, underground sensors are introduced to collect data and determine the type of material found at that depth. The rocks are then removed and passed to an initial laboratory where they are cleaned and are subsequently analyzed by microbiologists on board. Later, the rocks are taken to another laboratory for microbiological analysis.

 

Original Spanish article by Rodrigo Garcia Aranda.

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Slim Hole Reservoir Characterization for Risk Reduction

PROCEEDINGS, 41st Workshop on Geothermal Reservoir Engineering Stanford University, Stanford, California, February 22-24, 2016 SGP-TR-209 1

Presented by DOSECC President Dennis Nielson, Ph.D., PG and DOSECC Associate Sabodh K. Garg, Ph.D.

ABSTRACT:

High initial capital requirements and subsurface risk are commonly cited as significant impediments to more widespread development of hydrothermal resources. However, expensive production wells are often drilled at the early stages of development when risk is high. By drilling and testing slim holes at early stages, a developer can realize a significant reduction in risk at reasonable cost. In this paper, we will review different drilling approaches, their costs and impact on risk reduction. Slim holes have been promoted for reservoir characterization because of lower cost. However, they are also conducive to enhanced data collection that is critical for establishing conceptual models. Properly conducted injection tests provide reservoir engineering information that is equivalent to data collected from large well tests. When utilized in the reservoir testing phase, slim holes can provide greater volumetric sampling of a prospect than production-size wells at an equivalent cost. Therefore, significant risk reduction can be realized before the initiation of high-cost field development. Exploration is a knowledge-based activity and data collection and application to conceptual reservoir models is a requirement. We briefly discuss the data framework of the Play Fairway approach to demonstrate risk reduction.

slim hole drilling considerations

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Lake Towuti

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Lake Towuti Scientific Drilling Projecttowuti-scientific-drilling-project

lake-towuti-small-imageLake Towuti (2.5°S, 121°E) is a, 560 km2, 200-m deep tectonic lake at the downstream end of the Malili lake system, a set of five, ancient (1-2 Ma) tectonic lakes located in central Sulawesi, Indonesia. Lake Towuti’s location in central Indonesia provides an important opportunity to reconstruct long-term terrestrial paleoclimate change in a crucially important yet understudied region- the Western Pacific warm pool, heart of the El Niño-Southern Oscillation. Lake Towuti has high rates of floral and faunal endemism and is surrounded by one of the most diverse tropical forests on Earth making it a hotspot of Southeast Asian biodiversity. The ultramafic (ophiolitic) rocks and lateritic soils surrounding Lake Towuti provide ferruginous metal substrates that feed a diverse, exotic microbial community in the lake and its sediments, potentially analogous to the microbial ecosystems that operated in the Archean Oceans and on Mars.  The Towuti Scientific Drilling Program provided valuable new information to understand the climate, biological, and geomicrobiological evolution of this unique system.

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Read more about this scientific drilling project at Leibnitz Institute for Applied Geophysics.

Read more at ICDP.

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Lake Junin

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Lake Junin Scientific Drilling Project

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Lake Junín, located at ~4100 m asl in the inner tropics of the Southern Hemisphere, is a prime target for drilling because it contains a thick (>200 m) sediment package deposited at a high rate (0.2 to 1.0 mm yrF1). Moraine mapping coupled with cosmogenic radionuclide dating indicate that paleoglaciers reached the lake edge, but have not overridden the lake in one million years, or more. Lake Junín is thus one of the few lakes in the tropical Andes that predates the maximum extent of glaciation and is in a geomorphic position to record the waxing and waning of glaciers in nearby cordillera. The lake also contains ideal sediments for multiproxy analysis that can be reliably dated using both the radiocarbon and UFTh methods. The oxygen isotopic composition of marl and ostracod carapaces recovered in multiple preliminary cores covering the last 50 ka demonstrate that the d18O of authigenic calcite primarily records the isotopic composition of precipitation and secondarily the degree of evaporative enrichment of lake water. Lake Junín contains a continuous record of tropical hydroclimate over interglacial and interstadial intervals for much of the past several hundred thousand years that both complements and significantly extends stable isotope records from regional ice cores and speleothems.

Read more about this scientific drilling project at ICDP.

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Geothermal Play Fairway Analysis of the Snake River Plain, Idaho

Geothermal Play Fairway Analysis

 

GEOTHERMAL PLAY FAIRWAY ANALYSIS OF THE SNAKE RIVER PLAIN, IDAHO
Presented by Dennis L. Nielson, DOSECC President, at the Workshop on Geothermal Reservoir Engineering Stanford University, Stanford, California, January 26-28, 2015

ABSTRACT

Play Fairway Analysis is a systematic approach to exploration that integrates data at the regional or basin scale in order to define exploration targets (plays), and then interrogates these data to highlight plays that have the highest likelihood of success. Play Fairway Analysis provides greater technical rigor than traditional geothermal exploration approaches, and facilitates quantification of play risks even when data are sparse or incomplete. It is a mature practice in petroleum, but represents a new approach for geothermal that we believe will aid in the discovery of buried or blind systems. A key challenge will be adapting fairway analysis to geothermal exploration in a way that provides both meaningful results and measurable return on investment. In this project, we focus on the Snake River Plain where, during Project HOTSPOT, our team discovered a blind hydrothermal system at Mountain Home Air Force Base in Idaho. From that discovery we are able to define key parameters that characterize the elements necessary for a geothermal reservoir based on basaltic (plume-related) magmatism, fracturing that defines a reservoir volume, seals that are provided by lake beds, hyaloclastics, and highly altered clay-rich basalts, and fluid recharge that is controlled by faulting and the primary permeability of basalt flows. Project Hotspot identified three different play types in the SRP (a) high thermal gradients along the volcanic axis beneath the SRP aquifer, (b) extremely large low temperature systems, and (c) blind high-temperature systems like that discovered at Mountain Home. Phase 1 of this project will assess the distribution and viability of these plays throughout the SRP region; Phase 2 will focus on detailed analyses of specific plays as we move from a Regional/Basin focus to a Play/Prospect focus. Our approach is to analyze direct and indirect methodologies for identifying critical reservoir parameters: heat source, reservoir permeability, seal and recharge.

Read full publication here.