Andreas Morlok | University of Münster (original) (raw)
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Papers by Andreas Morlok
The files cover the mid-infrared spectra of bulk powders (Spectrum_MeltDroplet_) as in Figure 7a;... more The files cover the mid-infrared spectra of bulk powders (Spectrum_MeltDroplet_) as in Figure 7a; the single micro-FTIR spectra (Spectrum_) as in Figure 7b-d, the micro-FTIR maps (FTIR-map_) as in Figures 3 - 5b.
Icarus, 2016
Abstract This study is part of an effort to build a mid-infrared database (7–14 μm) of spectra fo... more Abstract This study is part of an effort to build a mid-infrared database (7–14 μm) of spectra for MERTIS (Mercury Radiometer and Thermal Infrared Spectrometer), an instrument onboard of the ESA/JAXA BepiColombo space probe to be launched to Mercury in 2017. Mercury was exposed to abundant impacts throughout its history. This study of terrestrial impactites can provide estimates of the effects of shock metamorphism on the mid-infrared spectral properties of planetary materials. In this study, we focus on the Nordlinger Ries crater in Southern Germany, a well preserved and easily accessible impact crater with abundant suevite impactites. Suevite and melt glass bulk samples from Otting and Aumuhle, as well as red suevite from Polsingen were characterized and their reflectance spectra in mid-infrared range obtained. In addition, in-situ mid-infrared spectra were made from glasses and matrix areas in thin sections. The results show similar, but distinguishable spectra for both bulk suevite and melt glass samples, as well as in-situ measurements. Impact melt glass from Aumuhle and Otting have spectra dominated by a Reststrahlen band at 9.3–9.6 μm. Bulk melt rock from Polsingen and bulk suevite and fine-grained matrix have their strongest band between 9.4 and 9.6 μm. There are also features between 8.5 and 9 μm, and 12.5–12.8 μm associated with crystalline phases. There is evidence of weathering products in the fine-grained matrix, such as smectites. Mercury endured many impacts with impactors of all sizes over its history. So spectral characteristics observed for impactites formed only in a single impact like in the Ries impact event can be expected to be very common on planetary bodies exposed to many more impacts in their past. We conclude that in mid-infrared remote sensing data the surface of Mercury can be expected to be dominated by features of amorphous materials.
Remote infrared observations allow us to obtain mineralogical information about micron-sized dust... more Remote infrared observations allow us to obtain mineralogical information about micron-sized dust in circumstellar environments like young stellar objects (YSO). Comparison to laboratory infrared measurements of meteorites material from the time when our own Solar System was an YSO provides a link between astronomical observations with the known compositions of extraterrestrial materials in our Solar System.
Meteoritics and Planetary Science Supplement, Sep 1, 2001
ABSTRACT Silicate-rich fragments from CI chondrites were analyzed with electron microprobe and TO... more ABSTRACT Silicate-rich fragments from CI chondrites were analyzed with electron microprobe and TOF-SIMS to investigate chemical heterogeneities in these meteorites. Considerable variations were found for most major elements, especially for S, K, Na and P.
To investigate the formation of chondrules in gas-grain collisions, we conducted experiments wher... more To investigate the formation of chondrules in gas-grain collisions, we conducted experiments where mineral mixtures were melted in plasma arcs. First results already show silicate-rich spheres quite similar to chondrules.
Mid-infrared spectra of matrix material from the Murchison CM2 chondrite, shocked with pressures ... more Mid-infrared spectra of matrix material from the Murchison CM2 chondrite, shocked with pressures from 10 to 49 GPa, were obtained. The results are compared to infrared spectra of dust from collisions in debris disks.
Spitzer and NASA/IRTF spectra of ~350 K circumstellar dust around the nearby MS star η Corvi (F2V... more Spitzer and NASA/IRTF spectra of ~350 K circumstellar dust around the nearby MS star η Corvi (F2V, 1.4 ± 0.3 Gyr) show clear evidence for warm, primitive, silicate-, water- and carbon-rich dust at ~3 AU, in the system’s Terrestrial Habitability Zone.
ABSTRACT We present the results of a study about the mid-infrared reflect ance properties of impa... more ABSTRACT We present the results of a study about the mid-infrared reflect ance properties of impact rocks from the zördlinger Ries impact crater. Spectra from separated components of suevite, melt glass, devitrified glass and matrix show a high degree of similarity, reflecting the high abundance of amorphous materials.
ABSTRACT We introduce IR/IS, a new facility for the study of planetary materials in the near- and... more ABSTRACT We introduce IR/IS, a new facility for the study of planetary materials in the near- and mid-infrared, focusing on the BepiColombo/MERTIS mission to Mercury.
ABSTRACT We compare mid-infrared spectra of dust in circumstellar disks and comets with FTIR abso... more ABSTRACT We compare mid-infrared spectra of dust in circumstellar disks and comets with FTIR absorbance spectra of components in primitive meteorites (CAI, chondrules, and matrix).
The files cover the mid-infrared spectra of bulk powders (Spectrum_MeltDroplet_) as in Figure 7a;... more The files cover the mid-infrared spectra of bulk powders (Spectrum_MeltDroplet_) as in Figure 7a; the single micro-FTIR spectra (Spectrum_) as in Figure 7b-d, the micro-FTIR maps (FTIR-map_) as in Figures 3 - 5b.
Icarus, 2016
Abstract This study is part of an effort to build a mid-infrared database (7–14 μm) of spectra fo... more Abstract This study is part of an effort to build a mid-infrared database (7–14 μm) of spectra for MERTIS (Mercury Radiometer and Thermal Infrared Spectrometer), an instrument onboard of the ESA/JAXA BepiColombo space probe to be launched to Mercury in 2017. Mercury was exposed to abundant impacts throughout its history. This study of terrestrial impactites can provide estimates of the effects of shock metamorphism on the mid-infrared spectral properties of planetary materials. In this study, we focus on the Nordlinger Ries crater in Southern Germany, a well preserved and easily accessible impact crater with abundant suevite impactites. Suevite and melt glass bulk samples from Otting and Aumuhle, as well as red suevite from Polsingen were characterized and their reflectance spectra in mid-infrared range obtained. In addition, in-situ mid-infrared spectra were made from glasses and matrix areas in thin sections. The results show similar, but distinguishable spectra for both bulk suevite and melt glass samples, as well as in-situ measurements. Impact melt glass from Aumuhle and Otting have spectra dominated by a Reststrahlen band at 9.3–9.6 μm. Bulk melt rock from Polsingen and bulk suevite and fine-grained matrix have their strongest band between 9.4 and 9.6 μm. There are also features between 8.5 and 9 μm, and 12.5–12.8 μm associated with crystalline phases. There is evidence of weathering products in the fine-grained matrix, such as smectites. Mercury endured many impacts with impactors of all sizes over its history. So spectral characteristics observed for impactites formed only in a single impact like in the Ries impact event can be expected to be very common on planetary bodies exposed to many more impacts in their past. We conclude that in mid-infrared remote sensing data the surface of Mercury can be expected to be dominated by features of amorphous materials.
Remote infrared observations allow us to obtain mineralogical information about micron-sized dust... more Remote infrared observations allow us to obtain mineralogical information about micron-sized dust in circumstellar environments like young stellar objects (YSO). Comparison to laboratory infrared measurements of meteorites material from the time when our own Solar System was an YSO provides a link between astronomical observations with the known compositions of extraterrestrial materials in our Solar System.
Meteoritics and Planetary Science Supplement, Sep 1, 2001
ABSTRACT Silicate-rich fragments from CI chondrites were analyzed with electron microprobe and TO... more ABSTRACT Silicate-rich fragments from CI chondrites were analyzed with electron microprobe and TOF-SIMS to investigate chemical heterogeneities in these meteorites. Considerable variations were found for most major elements, especially for S, K, Na and P.
To investigate the formation of chondrules in gas-grain collisions, we conducted experiments wher... more To investigate the formation of chondrules in gas-grain collisions, we conducted experiments where mineral mixtures were melted in plasma arcs. First results already show silicate-rich spheres quite similar to chondrules.
Mid-infrared spectra of matrix material from the Murchison CM2 chondrite, shocked with pressures ... more Mid-infrared spectra of matrix material from the Murchison CM2 chondrite, shocked with pressures from 10 to 49 GPa, were obtained. The results are compared to infrared spectra of dust from collisions in debris disks.
Spitzer and NASA/IRTF spectra of ~350 K circumstellar dust around the nearby MS star η Corvi (F2V... more Spitzer and NASA/IRTF spectra of ~350 K circumstellar dust around the nearby MS star η Corvi (F2V, 1.4 ± 0.3 Gyr) show clear evidence for warm, primitive, silicate-, water- and carbon-rich dust at ~3 AU, in the system’s Terrestrial Habitability Zone.
ABSTRACT We present the results of a study about the mid-infrared reflect ance properties of impa... more ABSTRACT We present the results of a study about the mid-infrared reflect ance properties of impact rocks from the zördlinger Ries impact crater. Spectra from separated components of suevite, melt glass, devitrified glass and matrix show a high degree of similarity, reflecting the high abundance of amorphous materials.
ABSTRACT We introduce IR/IS, a new facility for the study of planetary materials in the near- and... more ABSTRACT We introduce IR/IS, a new facility for the study of planetary materials in the near- and mid-infrared, focusing on the BepiColombo/MERTIS mission to Mercury.
ABSTRACT We compare mid-infrared spectra of dust in circumstellar disks and comets with FTIR abso... more ABSTRACT We compare mid-infrared spectra of dust in circumstellar disks and comets with FTIR absorbance spectra of components in primitive meteorites (CAI, chondrules, and matrix).