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Advances in the acquisition and processing of subseafloor temperature and pressure data and their interpretation in the context of convergent margin processes [Elektronische Ressource] / vorgelegt von Martin Heesemann

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DissertationAdvances in the acquisition and processing of subseafloortemperature and pressure data and their interpretation in thecontext of convergent margin processeszur Erlangung des Doktorgrades der Naturwissenschaftenam Fachbereich Geowissenschaftender Universität Bremenvorgelegt vonMartin HeesemannBremen, Juli 20087.7.2008Martin HeesemannWürzburger Str. 8628215 BremenErklärungHiermit versichere ich, dass ich1. die Arbeit ohne unerlaubte fremde Hilfe angefertigt habe.2. keine anderen als die von mir angegebenen Quellen und Hilfsmittel benutzthabe und3. die den benutzten Werken wörtlich oder inhaltlich entnommenen Stellen alssolche kenntlich gemacht habe.Bremen, den 7.7.2008ContentsKurzfassung 7Abstract 8Preface 91 Introduction 111.1 Temperature and pressure probes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111.1.1 Seafloor measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111.1.2 Borehole . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131.2 Analysis of temperature and pressure data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 151.3 Interpretation of and pressure data in the context of convergent margins . . . . . . . 161.3.1 Seismogenic Zone Experiment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 161.3.2 Subduction Factory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 161.4 Objectives of the thesis . .

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Dissertation
Advances in the acquisition and processing of subseafloor
temperature and pressure data and their interpretation in the
context of convergent margin processes
zur Erlangung des Doktorgrades der Naturwissenschaften
am Fachbereich Geowissenschaften
der Universität Bremen
vorgelegt von
Martin Heesemann
Bremen, Juli 20087.7.2008
Martin Heesemann
Würzburger Str. 86
28215 Bremen
Erklärung
Hiermit versichere ich, dass ich
1. die Arbeit ohne unerlaubte fremde Hilfe angefertigt habe.
2. keine anderen als die von mir angegebenen Quellen und Hilfsmittel benutzt
habe und
3. die den benutzten Werken wörtlich oder inhaltlich entnommenen Stellen als
solche kenntlich gemacht habe.
Bremen, den 7.7.2008Contents
Kurzfassung 7
Abstract 8
Preface 9
1 Introduction 11
1.1 Temperature and pressure probes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
1.1.1 Seafloor measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
1.1.2 Borehole . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
1.2 Analysis of temperature and pressure data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
1.3 Interpretation of and pressure data in the context of convergent margins . . . . . . . 16
1.3.1 Seismogenic Zone Experiment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
1.3.2 Subduction Factory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
1.4 Objectives of the thesis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
1.5 Outline and strategy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
2 Measurement of temperatures and pressures 20
Publication: Testing and deployment of the new APCT-3 tool to determine in-situ temperatures while
piston coring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Publication: Long-term temperature measurements in Holes 1253A and 1255A off Costa Rica, ODP
Leg 205 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
3 Analysis of temperature and pressure data 61
Manuscript: Estimation of in-situ formation temperatures from transient tool response in unconsoli-
dated sediments during piston coring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
Software: TP-Fit Version 1.0, a free software package to estimate undisturbed formation temperatures
from downhole tool measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90
Manuscript: Estimating in-situ formation pressures from penetration transients of a borehole probe . . 96
4 Interpretation of temperature and pressure measurements 109
Manuscript: Thermal constraints on the frictional conditions of the nucleation and rupture area of the
1992 Nicaragua tsunami earthquake . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109
Publication: Alteration of the subducting oceanic lithosphere at the southern central Chile trench-outer
rise . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 124
Publication: Fluid flow through active mud dome Mound Culebra offshore Nicoya Peninsula, Costa
Rica—evidence from heat flow surveying . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144
5 Conclusions and Outlook 158
5.1 Acquisition and processing of temperature and pressure data . . . . . . . . . . . . . . . . . . . 158
5.2 Interpretation of temperature and pressure data . . . . . . . . . . . . . . . . . . . . . . . . . . 159
Bibliography 160
Danksagung 165
5Lebenslauf 166Kurzfassung
Temperatur und Druckmessungen am Meeresbo- denen Sonden deutlich besser wider. Außerdem ist es
den liefern uns wichtige Informationen über dynami- mit TP-Fit möglich Daten aller derzeit im Rahmen
sche Prozesse im Erdinneren. Um an diese wertvol- von ODP/IODP im Einsatz befindlicher Sonden in ei-
len Daten zu gelangen, werden zuverlässige Sonden, ner konsistenten Art und Weise zu prozessieren. Das
die hoch auflösende Messwerte liefern, benötigt. Au- Programm ist modular ausgelegt, um nachträgliche
ßerdem sind Fehlerkorrekturverfahren erforderlich, Erweiterungen, z.B. in Hinblick auf neue Tempera-
die Störungen der Messdaten, welche beim Eindrin- tursonden oder das Prozessieren von DVTPP Druck-
gen der Sonden in den Meeresboden entstehen, kor- daten, zu vereinfachen.
rigieren. Letztendlich müssen die Temperatur und Um aus Meeresbodentemperaturmessungen etwas
Druckmessungen, zusammen mit Informationen aus über Prozesse an konvergenten Plattenrändern zu ler-
anderen geophysikalischen Messungen und geologi- nen, wurden die Messungen mit andere geophysika-
schen Beobachtungen, im Rahmen von konzeptionel- lische und geologische Beobachtungen in einem neu-
len oder numerischen Modellen interpretiert werden, en FE Modell kombiniert. Das Ziel der Modellierung
damit wir aus ihnen etwas über geologische Prozesse war es die Temperaturverteilung an der Bruchfläche
lernen können. des Tsunami-Erdbebens, das 1992 vor der Küste Ni-
caraguas stattfand, abzuschätzen. Diese Temperatur-Beispiele für moderne Druck- und Temperatur-
verteilung ist eine wichtige Einflussgröße, die diesonden sind das Advanced Piston Corer Tempera-
obere Grenze der seismogenen Zone—der Bereichture Tool in der 3. Version (APCT-3), der Minia-
der Plattengrenze an einer Subduktionszone, in demturized Temperature Logger (MTL) und die Davis-
es durch bruchhafte Verformung zu Erdbeben kom-Villinger T and Pressure Probe (DVTPP).
men kann—bestimmt. Im Vergleich zu anderen ther-Das APCT-3 setzt neue Standards in den Bereichen
mischen Modellen von Subduktionszonen zeichnetGenauigkeit, Auflösung und Zuverlässigkeit, was die
sich das neue Modell durch die detaillierte Abbil-Messung von Temperaturen während der Kernent-
dung der Strukturen im graben nahen oberen Bereichnahme in Integrated Ocean Drilling Program (IODP)
der Subduktionszone aus. Dies ist der Bereich in demBohrlöchern angeht. MTLs sind aufgrund ihrer ho-
sich auch die Obergrenze der seismogenen Zone be-hen Langzeitstabilität und Auflösung hervorragend
findet.dafür geeignet Temperaturen in marinen Bohrlöchern
Außerdem wurden Messungen von Meeresbo-über lange Zeiträume zu beobachten. Das DVTPP ist
dentemperaturen dazu verwendet, um Massen- unddie erste Bohrlochsonde, die im Rahmen des Ocean
Energieströme, die in Subduktionszonen ein- undDrilling Program (ODP) dazu verwendet wurde, um
austreten, zu detektieren. Z.B. wurde anhand vonIn-situ Formationsporendrücke zu messen.
Temperaturmessungen das Eintreten von kaltem
TP-Fit ist ein neues Programmpaket, das es er- Meerwasser in die ozeanische Kruste am „Outer-
möglicht Temperaturdaten von Bohrlochsonden in rise“ vor der Küste im Süden Chiles nachgewiesen.
Hinsicht auf die während des Eindringens der Son- Zusammen mit der Beobachtung von niedrigen seis-
den entstehenden Störungen zu korrigieren. Im Zuge mischen Krustengeschwindigkeiten in diesem Be-
der Entwicklung von TP-Fit wurden außerdem zum reich wurde die These entwickelt, dass die ozeani-
ersten Mal systematisch die Fehler, die bei der Ana- sche Kruste und der obere Mantel vor ihrer Subduk-
lyse von Bohrlochtemperaturdaten auftreten können, tion durch zahlreiche Brüche und Hydrierung durch
erfasst und quantifiziert. TP-Fit basiert auf numeri- Meerwasser verändert werden. In einem anderen
schen Modellen der Temperatursonden, die mit Hil- Beispiel wurden Fluidströme durch den Schlamm-
fe der Finite Elemente (FE) Methode berechnet wur- kegel Mound Culebra, der sich am Kontinentalhang
den. Im Vergleich zu Modellen die in älteren Pro- vor der Costa Ricanischen Halbinsel Nicoya befin-
grammen zur Abschätzung der ungestörten Forma- det, u.a. durch die Interpretation von Temperaturmes-
tionstemperatur benutzt wurden, spiegeln die neuen sungen nachgewiesen.
FE Modelle die komplexen Geometrien der verschie-
7Abstract
Subseafloor temperature and pore fluid pressure ature field at the subduction thrust fault of the 1992
data can provide important constraints on most dy- Nicaragua tsunami earthquake. Fault temperature is
namic earth processes. Acquiring this data using di- a controlling factor of the updip limit of the seis-
rect measurements requires reliable probes that mea- mogenic zone—the portion of the interface between
sure accurate data with high resolution. Additionally, the subducting and the overriding plate at convergent
algorithms to correct for disturbances—created dur- margins that produces earthquakes via stick-slip slid-
ing probe insertion into the formation of interest— ing. Compared to previous thermal models of sub-
are needed. Finally, to expand or knowledge about duction zones, the model focuses particularly on de-
earth processes, the measured data have to be com- tails that effect the temperature distribution close to
bined with geologic findings and data from other the trench where the updip limit of the seismogenic
geophysical surveys using conceptual or numerical zone is located.
models of the studied processes. Subseafloor temperature measurements can be
used to detect mass and energy inputs and outputs ofExamples for modern temperature and pressure
subduction zones. For example, cold seawater infil-probes are the third version of the Advanced Pis-
trating oceanic crust was detected using temperatureton Corer Temperature probe (APCT-3), the Minia-
data at the southern Chile trench-outer rise. This sup-turized T Logger (MTL), and the Davis-
ported the interpretation of reduced seismic veloci-Villinger Temperature and Pressure Probe (DVTPP).
ties as evidence that structures of the oceanic crustThe development of the APCT-3 sets new standards
and the uppermost mantle are altered by fracturingin accuracy, resolution, and reliability for measur-
and hydration before they enter the subduction zone.ing temperatures during piston coring in Integrated
In another example, active fluid venting through theOcean Drilling Program (IODP) boreholes. MTLs
mud dome Mound Culebra, located on the continen-provide innovative means for long-term monitoring
tal slope offshore Nicoya Peninsula, Costa Rica, wasof borehole temperatures offering high resolution and
inferred from subseafloor temperature measurementsexcellent long term stability. The DVTPP is the first
along with data from other geophysical surveys anddownhole tool that is capable to measure in-situ for-
gravity coring.mation pore pressures in Ocean Drilling Program
(ODP) boreholes.
TP-Fit is a new software package capable to cor-
rect temperature data of downhole tools for the dis-
turbance created during insertion into the formation.
During the development of TP-Fit, the accuracy of
data analysis algorithms to process downhole tem-
perature data was studied systematically, for the first
time. TP-Fit uses finite element (FE) method models
of the probes’ thermal responses for the data analysis
that represent the probes geometry better than refer-
ence models used in prior software packages. Using
TP-Fit it is possible to process data from all temper-
ature probes currently in use in the ODP/IODP con-
sistently within a single software. Moreover, the pro-
gram structure is modular and allows future additions
as the processing of DVTPP pressure measurements.
Combining subseafloor temperature measure-
ments with other geophysical and geological data, a
thermal FE model was used to estimate the temper-
8Preface
When I started to work on my PhD thesis in development of the APCT-3, which progressed more
Summer 2002, the initial plan was to continue the slowly than anticipated, was continued as part of the
work I had done during my diploma thesis „Model- continuation project TEMPO II.
ing and analysis of transient pressure measurements
During the same time I also had the opportunity
in ODP boreholes for undisturbed formation pres-
to participate in IODP Expedition 301T (August–
sure estimation“ (Heesemann, 2002) and to carry
September 2004), a short leg on the transit between
it on to a broader level in the frame of the DFG
two Expeditions to recover longterm temperature and
funded Temperature Probes of the ODP (TEMPO)
fluid sampling observatories from ODP Sites 1253
project. I should have participated in Ocean Drilling
and 1255, off Costa Rica. On this expedition, I had
Program (ODP) Leg 204 (July–September 2002) to
the chance to learn at first-hand how operations on
measure formation temperatures and pressures with
a drill ship, that I only knew in theory, work. I was
the APCT, DVTP, and DVTPP tools. Next steps
also able to connect one part of my prior research
would have been to develop enhanced processing al-
interests, measuring temperatures and pressures in
gorithms to extrapolate the measured data to undis- marine boreholes, with the other part, the thermal
turbed formation values, to process the data with the
structure of the subduction zone, off Costa Rica and
new algorithms, and to interpret the data in the sci-
Nicaragua.
entific context (gas hydrates) of the Leg 204. Mean-
After the MAMAST project ran out, I joined thewhile, I should have supported the development of
BMBF funded „from The Incoming Plate to mega-the APCT-3, an enhanced APCT tool. But right from
Thrust EarthQuake processes“ (TIPTEQ) project.the start things did not work out as anticipated and
During TIPTEQ I continued to refine the thermalthe following research continued on winding paths
model of subduciton zones using constraining heat-that took a while to travel.
flux measurements that I helped to acquire dur-
First of all, my application for the ODP Leg, ing RV-Sonne cruise SO-181-1b (December 2004–
even though strongly supported by the co-chief sci- January 2005). Meanwhile, the development of
entist Prof. Dr. Gerhard Bohrmann, was rejected. the APCT-3 tool has been finished. This was just
There was still hope, that I could use the measured in time, so that first measurements with the proto-
data as shore-based scientist and carry out the ini- type could be made during IODP Expedition 311
tial plan after the end of Leg 204. In order to fill (August–October 2005) and the India gas hydrate
the time gap, I participated in RV Meteor cruise Leg (May 2006), before the JOIDES Resolution was
M54-2 (August–September 2002) with funding from brought to a shipyard for extensive remodeling. Pro-
the Middle America Margin Subsurface Temperature pelled by the success of the APCT-3 tool, I refo-
(MAMAST) project. During this time I helped to cused on the data analysis of the temperature data,
measure and to process seafloor heat-flux data, off since none of the old programs could handle the
Costa Rica. However, after Leg 204 has ended, there data from the new tool properly. The outcome was
was no data for me to work with, since my request TP-Fit, a program to extrapolate undisturbed forma-
to use the temperature data as a shore-based scien- tion temperatures from measurements of all kinds
tist was rejected and most of the pressure measure- of tools commonly used during the ODP/IODP. The
ments did not work out properly; most of them were feed-back on TP-Fit from the scientific community
affected by an plumbing error inside of the DVTPP. was very encouraging. Therefore, by the time the
So I decided to focus my research on the interpre- TIPTEQ project ran out in July 2007, I accepted an
tation of the MAMAST heat-flux data. I developed offer from the IODP/TAMU to implement some fur-
a finite element model for the thermal state of sub- ther enhancements in TP-Fit as contract work. This
®duction zones based on the Femlab toolbox (now work resulted in a better integration of the software,
®COMSOL-Multiphysics )—which I already knew with the shipboard work flow and the database sys-
from the work in my diploma thesis—during the con- tem.
tinuation project MAMAST II. At the same time, the
9If my application for ODP Leg 204 would not have
been rejected, that path to this thesis would probably
have been much straighter and shorter. But the way
it was, I have covered a lot more scientific ground,
which is also reflected in the unusually broad subject
of the thesis. Moreover, I am grateful for the oppor-
tunities I had to spend time with so many wonderful
people from all over the world and from different sci-
entific communities along the way.