Micropaleontology

Macro- and Micropaleontological analyses of smear slides, thin sections and other materials will be carried out in the microscopes lab. Below some examples of available microscopes are shown. Please note that we will try to organize any microscope for your special requirement.

The lab is equipped with a hot plate under hood, a variety of permanent mounting media, and supplies (petrographic slides, cover glasses, sieves, sampling tools, etc.) for the preparation of smear slides.

Smear slides: permanent mounts of fine (silt- and clay-sized) granular sediment. Smear slides are generally made from samples of well-sorted, fine-grained clastic and biogenic sediments (mud, ooze, micrite, etc.). They can also be made from the fine-grained fractions that are mechanically extracted (by sieving) from more poorly sorted sediments.

Preparation of a smear slide requires an extremely small ("toothpick") sample. To make smear slides, the following supplies and equipment are needed:
1. cover glass (24 x 40 mm) - #1 thickness
2. toothpick
3. water dropper
4. glass petrographic slide (25 x 75 mm)
5. permanent mounting medium
6. glass rod
7. hot plate
8. tweezers
9. pencil with new eraser
10. slide label

The hot plate is located under a hood. The hot plate should be set constantly on "low." A small beaker or uncapped bottle of mounting media is usually kept on (if appropriate, to reduce its viscosity) or near the hot plate under the hood at all times.
To make a smear slide take a cover glass in hand and place a few drops of distilled water in its center. Collect a tiny fraction of the sample with the flat end of the toothpick, and mix it into the water on the cover glass. Spread the wet sediment with the flat end of the toothpick until it forms a thin translucent coat across the entire cover glass, and then place the cover glass (with the sediment smear up) on the surface of the hot plate to dry.
While the smear on the cover glass dries, place a slide label on the glass petrographic slide, and label it with the expedition site, hole, core, core, type, section, and sample interval data. Place a few drops of mounting medium in the center of the petrographic slide with the glass rod, and set
it on the surface of the hot plate to warm. When the smear on the cover glass is dry, use the tweezers to place the cover glass (with the sediment smear down) on the mounting medium on the petrographic slide. Press down and slowly rotate the cover glass with the clean eraser-end of the pencil
to spread the mounting medium across the petrographic slide and to expel gas bubbles. If there is not sufficient mounting medium to cover the entire smear, use a clean toothpick to drip one or two drops of mounting medium
onto the petrographic slide at the edge of the cover glass, where they will be drawn by capillary action under the cover glass. Finally, return the smear slide to the hot plate for 3-5 minutes to allow it to cure.

Thin sections will be made on request in the building of the Faculty of Geosciences at Bremen University, which is located 100 m from the MARUM.

The Olympus BH-2 is a stereo microscope suitable for polarization microscopy.

The Olympus BX-51 is a stereo microscope suitable for polarization microscopy equipped with an Olympus DP-20 digital camera.

The Olympus BX-41 is a stereo microscope suitable for phase contrast analyses. The camera from BX-51 can be installed easily on this microscope.

The Zeiss Stemi 2000 is a stereo microscope with reflected light illumination.